how to solve logs mcat

Quickly Calculate Logarithms Without a Calculator | MCAT Tips and Tricks

Last Updated on June 24, 2022 by Laura Turner

Logarithms are one of the most difficult math topics on the MCAT because many of us haven’t studied them since high school and probably never learned how to calculate logarithms without a calculator.

This is a good news/bad news situation. The bad news is that pH and sound intensity problems from general chemistry and physics will require you to work with logarithms without a calculator. The good news is there’s a trick that makes calculating logarithms easy and will amaze your friends with your mental math skills.

First a quick review of what logarithms are and why they are important on the MCAT: The common logarithm or “log” operator (sometimes seen as “log 10 “) is most useful when describing something that is measured on a very large scale.

Mastery of logarithms was essential for scientists and engineers in the 19th and early 20th centuries because they could be used to simplify all kinds of complex calculations. Modern computers have made those skills obsolete, but common logarithms still appear in problems like pH calculations where the underlying scale changes according to powers of 10.

In chemistry, acidity can be measured on a linear scale from [H+] = 0.00000000000001M to [H+] = 1M. However, a 1M difference in [H+] isn’t really meaningful. We see real differences in acidity between substances when the [H+] of one is 100 or 1000 (or more!) times greater than the [H+] of the other.

Calculating PH allows us to measure acidity on a log scale of pH=14 to pH=0. Just as it makes more sense to measure the distance between Tokyo and London in miles rather than inches, it is more useful to describe acidity using pH rather than [H+].

So how exactly does this work? The log function is used to solve equations where the variable is an exponent with base 10. For example, 10 X = 100. The log operator allows us to solve for X and write an equivalent expression as log(100) = X. 10 X = 100 is the exponential form of the expression, and log(100) = X is the logarithmic form.

It is easiest to determine the logarithm of a power of 10 because the solution is equal to the power of the exponent. Continuing the example above, we can solve the equation by rewriting log(100) as log(10 2 ) = 2.

Of course, on the MCAT, you’ll be required to approximate the log of values that are not simple powers of 10. Note the key word here is approximate . One of the most important principles of mastering MCAT math is remembering that you don’t have to calculate the exact answer to every problem, you just need to get close enough to select the correct answer from the list of possible choices.

Recall that pH is the negative log of the [H+]. We can approximate the negative log of a quantity using the formula

–log(m x 10 -n ) ≈ n – 0.m

where m is a number between 1 and 10 and n is an integer (a whole number).

Some quick examples using the approximation:

–log(3 x 10 -5 ) ≈ 5 – 0.3 = 4.7 –log(7.1 x 10 -9 ) ≈ 9 – 0.71 = 8.29 –log(2.5 x 10 -2 ) ≈ 2 – 0.25 = 1.75

That’s all there is to it!

Let’s end with a couple pH problems:

We hope that these instructions on how to calculate logarithms without a calculator help you crush the MCAT! Make sure to check out the rest of the MCAT Tips and Tricks Series:

• Part I – Converting between units in the metric system
• Part III – Using approximation to tackle complex calculations
• Part IV – Unit conversions in eight easy steps
• Part V – The one about trigonometry

Want to learn more about how to succeed on the MCAT? Check out this webinar from Student Doctor Network and MedSchoolCoach that breaks down key factors for a great score

Text Version of Quiz

Q: What is the pH of a 4.2 x 10 -3 M HNO 3 solution?

a) 1.61 b) 2.38 c) 3.42 d) 4.20

A: Because HNO 3 is a strong acid, [H+] = 4.2 x 10 -3 M.  The pH of a solution is equal to the negative log of the concentration. In this case, pH = –log(4.2 x 10 -3 ). Using the approximation, we can solve –log(4.2 x 10 -3 ) ≈ 3 – .42 ≈ 2.5, which is closest to answer b).

Q: The K a of an acid whose buffer has a pH of 3.62 in a solution containing equal M of acid and conjugate base is closest to:

a) 1.02 x 10 -7 b) 3.62 x 10 -5 c) 2.40 x 10 -4 d) 7.23 x 10 -2

An important thing to note in this problem is that, when an acid is in a solution containing equal quantities of the acid and conjugate base, the pH is equal to the pK a .

Therefore, we have pH = 3.62 = pK a . However, we are trying to solve for the K a , not the pK a (recall also that pK a = –log(K a ) ), and we will need to use the approximation we learned before but in reverse.

pH = n – 0.m ≈ –log(m x 10 -n )

We can rewrite the pH of 3.62 as 4 – 0.38, putting it in the form n – 0.m shown above.  This gives us

pH = 4 – 0.38 ≈ –log(m x 10 -n )

Now we can substitute in m and n to approximate K a on the right hand side.

pH = 4 – 0.38 ≈ –log(3.8 x 10 -4 )

So the approximate value of the K a is 3.8 x 10 -4 M, which is closest to answer c).

Chelsea Myers, M.Stat, is the author of the MCAT Math eBook series available at www.mcatmath.com . After a decade-long career as a research biostatistician in the Department of Ophthalmology and Visual Sciences at the University of Wisconsin – Madison, she is currently a professor of mathematics, statistics and biostatistics at Rollins College and Valencia College in Florida. She lives with her husband and three sons in the Orlando area.

1 thought on “Quickly Calculate Logarithms Without a Calculator | MCAT Tips and Tricks”

The last example says the answer is c, but 3.8 x 10-4 M is not listed as answer c (or any of the answers). Is this a typo…?

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MCAT Math Tips from the Nation’s Leading Tutor

Posted in: MCAT

Table of Contents

Preparing for the MCAT (Medical College Admission Test) involves mastering a variety of subjects, including biology, chemistry, physics, biochemistry, organic chemistry, psychology, and sociology. You’re required to take most of these subjects as undergraduate courses, but math isn’t one of them.

Many students overlook just how much math is on the MCAT or get worried because they had a difficult time in previous math classes.

Don’t be overwhelmed! In this comprehensive guide, we’ll cover everything you need to know about MCAT math, from rounding to manipulating equations.

Want MCAT tutoring from the best tutors in the U.S.? You’ve found the right place.

You only get scratch paper on test day.

You’ll need to find the correct answer to each math-related question by using only scratch paper. You will not get a calculator for the MCAT.

The AAMC calls their special scratch paper the ‘MCAT Test Day Noteboard Booklet’. It’s a laminated booklet that comes with a wet-erase pen and plenty of space to write out your calculations.

Many students feel terror wash over them when they realize there’s no calculator allowed for the MCAT. But the absence of a calculator is good news in disguise — it means the level of calculations has to be relatively simple.

In order to use the Noteboard Booklet efficiently, there are 2 things you need to be able to do:

• During your MCAT prep, you may need to relearn math concepts you haven’t seen since high school. This includes basic trigonometry, logarithms, exponents, scientific notation, and fundamental algebra.
• You need to do a lot of realistic practice questions and problems that require manual calculations during your study time . This will help prevent you from over-relying on mental math during test day.

We spent dozens of hours developing the most accurate MCAT practice exam to simulate the questions you’ll encounter on test day.

What kinds of math are required for the mcat.

The key math topics and calculations found on the MCAT include: 

• Basic arithmetic (addition, subtraction, multiplication, division, fractions, proportions, square root estimations, ratios, and percentages)
• Trigonometry
• Statistics and probability
• Scientific notation
• Coordinate geometry

There is no calculus or other advanced math on the MCAT.

MCAT math topics are designed to test reasoning abilities that are important for your success in medical school and as a physician. Top scorers develop a good number sense, which is the ability to think flexibly and critically about numbers and estimation.

Let’s take a look at how to approach some of the most important math rules and equations you’ll need for the MCAT.

1. Rounding

Rounding is your best friend — it shows up in virtually every type of MCAT math question.

The exam is not testing how precisely you can calculate values using complex numbers. Instead, rounding to friendly numbers (often whole numbers) is the way to go and is expected by the test makers. You can see this clearly in AAMC answer choices, as they are often approximations.

How much can you round on the MCAT? When rounding a number, it will always be safe to round up or down by 10% of the number you’re rounding.

For example: A passage describes Metformin, a medication to treat Type II diabetes, that has a molar mass of 165.62 g mol -1 . You’re asked to find how many moles of the medication a patient will ingest if they take 625 milligrams twice daily.

Using our rounding rule, we know that 165.62 can be rounded up or down by 16.562. A good number sense tells us that rounding down to 150 is an easy number to work with. 625 can be rounded up or down by 62.5, so we choose to round down to 600.

This means you’re now working with the numbers 150 and 600 — which is much easier than 165.62 and 625.

Related: Factors to Consider Before Signing up for Your MCAT Test Date

2. Scientific Notation

When dealing with numbers that have many digits or working with numbers that are either very large or very small, scientific notation will save you a lot of headaches. It helps simplify calculations, comparisons, and representation of numerical data.

For instance, if you’re asked to multiply 0.000008 by 15,000, start by changing these numbers to something easier to work with. Try (8.0 x 10 -6 ) x (1.500 x 10 4 ).

Now, we can multiply the whole numbers and the exponents separately:

• 8 x 1.5 = 12
• Adding our exponential terms together, we get 10- 2
• The answer is quickly solved to be 12 x 10 -2 , or 1.2 x 10 -1

Sometimes, you will need to manipulate the order of magnitude of a number that is in scientific notation. The rule is that when you move a decimal place to the right (making the coefficient larger), the exponent becomes smaller: 4.562 x 10 4 is the same number as 4562 x 10 1 .

On the flip side, when moving the decimal to the left and making the coefficient smaller, the exponent becomes larger: 782 x 10 1 is the same number as 7.82 x 1 3 .

Read Next: High-Yield MCAT Topics and How to Study

3. Multiplication

Multiplication on the MCAT is typically simple, though checking your answer on paper is usually a good idea to ensure you didn’t make a silly mistake! There’s no shame if your times tables through 12 are rusty — set aside a little time to work through them until they’re automatic.

You may need to multiply two-digit numbers without rounding, which can be a bit tricky if you’re out of practice.

Here is an MCAT multiplication trick that helps make it more manageable:

Multiplying 32 x 17 might seem calculator-level, but it’s not! Mental math experts suggest turning this type of problem into a two-step math problem: 32 x 10 + 32 x 7. After all, multiplication is just fancy addition.

32 x 10 + 32 x 7 = 320 + 32 x 7

If you get stuck at 32 x 7, our strategy keeps working by turning this problem into:

32 x 10 + 30 x 7 + 2 x 7 = 320 + 210 + 14

The answer to this longer (but simpler) equation is 544.

With a bit of practice, you’ll be able to multiply any two-digit number with ease!

4. Division

Division is just as common as multiplication on test day . Thankfully, long division will not show up on your MCAT, as that would take too much time.

One option to simplify division problems is to use rounding. For instance, if you’re asked to divide 2209 N by 743 m/s 2 , you can round that to 2100 N / 700 m/s 2 . This is equivalent to the fraction 21 N / 7 m/s 2 , which is obviously equivalent to 3 N / 1 m/s 2 or 3 kg. Based on this, you know the answer will be close to 3 kg.

Another MCAT division strategy involves thinking through how many times the denominator “goes into” the numerator. For instance, if you’re asked to solve 141 / 30, here’s how to go about it:

• Ask ‘how many times does 30 go into 141?”
• We can see that it goes in once (30), twice (60), three times (90), and four times (120) but not five times.
• From here, we try ½ of 30 and we see that 120 + 15 = 135.  We should probably stop here and say the answer is roughly 4.5, but we could keep going and determine whether ¼ of 30 would get us closer to 141.

5. Dividing Exponents

Division of numbers in exponent form just involves fairly simple subtraction. From our previous discussion on rounding, let’s try to divide 600 mg / 150 g mol -1 .

• First, we’ll need to fix our units using orders of magnitude: 600 mg is the same as 6 x 10 2 mg, but we need it in grams. The conversion factor here is 1 x 10 -3 , giving us 6 x 10 -1 g.
• We end up with (6 x 10 -1 ) / (1.5 x 10 2 ). Note the manipulation of 150 so that it is smaller than the numerator coefficient.
• Now, we figure out how many times 1.5 goes into 6. We can see that it goes in 4 times evenly, but what do we do with the exponents? When dividing exponents, subtract them, and when multiplying, add them together.
• This gives us our final answer of 4 x 10 -3 moles.

Related: MCAT Score Conversion Calculator

6. Trigonometry

The MCAT wants you to be able to show a comprehensive grasp of the fundamental trigonometric principles, including:

• Defining basic trigonometric functions such as sine, cosine, and tangent, as well as their inverses (sin⁻¹, cos⁻¹, tan⁻¹).
• Identifying the sine and cosine values at key angles: 0°, 90°, and 180°.
• Understanding the relationships between the lengths of the sides of right triangles that involve angles of 30°, 45°, and 60°.

We can only use these trigonometric functions with right triangles. The functions are the ratios of the triangle side lengths:

• sin(θ) = opposite/hypotenuse
• cos(θ) = adjacent/hypotenuse
• tan(θ) = opposite/adjacent

A common mnemonic to remember this is SOH CAH TOA. The inverse functions are:

• sin-1(θ) = hypotenuse/opposite
• cos-1(θ) = hypotenuse/adjacent/
• tan-1(θ) = adjacent/hypotenuse

7. Logarithms

A logarithm is a mathematical function that represents the exponent to which a specified base must be raised to produce a given number. The logarithm base 10, often denoted as “log base 10” or simply “log,” calculates the exponent to which the base 10 must be raised to yield a specific number.

Logarithms on the MCAT are always log base 10 or, on occasion, the natural log (ln). The general form of the equation is log 10 (x) = y, where x is the number for which the logarithm is being calculated, and y is the exponent to which 10 must be raised to produce x.

@mcat_basics MCAT Math can really suck sometimes Ngl…use this trick to make your life way easier and check out @MedSchoolCoach ‘s formula sheet! #premed #premedadvice #premedsoftiktok #premedtips #premedstudent #premed #medschoolapp #medschooladvice #premedmotivation #medschoolapps #medschoolapplication #medschooladmissions #medschool #medstudent #medicalstudent ♬ original sound - Luke | Your MCAT Prep Guide

Mastery of logarithms is essential for answering questions about acid-base chemistry as well as other physics and chemistry topics. They are particularly useful for simplifying calculations involving very large or very small numbers. 

Certain log (and natural log) properties are useful to memorize: 

• When taking the log of a number that is > 1, the answer will be positive. 
• When taking the log of 1, the answer is zero.
• When taking the log of a number < 1, the answer will be negative.
• You can’t take the log of a number <0

MCAT Prep by MedSchoolCoach is a mobile-first MCAT study tool with videos, flashcards, question banks, and everything else you need to prepare for test day.

The best problem-solving strategies for mcat math.

Questions that require numerical problem solving typically come in the Chemical and Physical Foundations of Biological Systems Section (Chem/Phys for short). Being able to quickly identify the correct equation(s), numbers, and mathematical setup is crucial.

• Practice makes perfect. The most important strategy is the most obvious: Practice! You should complete practice problems multiple days a week during your MCAT prep. Review your practice test results and use of scratch paper to improve the speed of your calculations. Follow a foolproof study plan with ample time to hone your math skills and boost your percentile score .
• Memorize your MCAT physics and chemistry equations. Make a point to write them out from memory. An equation will often have to be manipulated algebraically to solve for a particular variable. The best equation strategy is to complete all of the algebraic manipulations of an equation before trying to plug in numbers. This will allow you to cancel out terms that may appear on both sides of the equation. (Download our complete guide to every Chem/Phys equation you need to know for the MCAT.)

Let’s look at an example: If asked for the final velocity of an object during free fall, we can use kinetic and potential energy equations, 1/2mv 2 and mgh respectively.

A quick setup of the two equations gives us mgh = 1/2mv 2 .

We know we’re solving for v, but before we start to rearrange the relationship, notice the mass terms cancel out, leaving us with gh = 1/2v 2 .

Next, we move the ½ and exponential terms to give v = √2gh. Only now should you plug in the relevant numbers and do the math. 

• Use mental mental shortcuts. Mental math tricks can help you develop good, consistent number sense. Dedicate time to practicing mental math during your study week. Start with simple arithmetic operations such as addition, subtraction, multiplication, and division, and gradually increase the complexity of the problems as you become more comfortable.
• For example, the addition and subtraction shortcut. When adding 7, 8, or 9 to a number, try to think of it as adding 10, and then subtracting the difference. For example, instead of 74 + 8, try 74 + 10 – 2. This also works for subtraction — instead of subtracting 7, 8, or 9 from a number, subtract 10 and add the difference. 346 – 127 should be taken in two steps: 346 – 120 = 226, and then 226 – 10 + 3 = 219.
• Or the logarithm shortcut. Sometimes you’ll be asked to find the log of a number that isn’t a multiple of 10. Consider log(7), for instance. What do you do in this scenario? One simple trick is to realize that the log of any number between 1 and 10 is going to work out to somewhere between 0 and 1. For simplicity’s sake, let’s estimate log(7) to be 0.5. This can help us evaluate the log of longer expressions. Consider log(7 x 10 5 ) as an example. If we estimate log(7) to be 0.5, then we know log(7 x 10 5 ) will be roughly equal to 0.5 + log(10 5 ). And since the log of any exponent of 10 is simply the exponent itself, we can estimate the answer to be 0.5 + 5 or 5.5.

Read Next: How Many Times Can You Take the MCAT? Yearly/Lifetime Limits

No, there is generally no calculator provided on the MCAT. Special testing accommodations from the AAMC may allow a calculator.

The math on the MCAT is very simple, but that doesn’t mean it’s easy! Although MCAT math is high school level, the short time you have to solve problems can make even simple math difficult.

If you follow my tips above, you’ll be able to more easily answer MCAT questions with math, even without a calculator. This includes practicing (a lot), rounding by up to 10% of the original numbers to make them easier to work with, using scientific notation, and memorizing formulas and basic trigonometry and logarithmic equations.

There are a lot of formulas and equations you need to know for the MCAT. Download a complete list here . 

Be sure to spend time with each one that you encounter during your test prep. Know the equation, units, and the scenarios in which they are used.

Get MCAT Tutoring from 99th Percentile Tutors

MCAT prep doesn’t have to feel daunting — our tutors can teach you additional shortcuts and tips for mastering MCAT math.

Let our 99th-percentile tutors help you increase your MCAT score by 12 points or more!

Ken Tao, PhD

Ken is the Director of MCAT at MedSchoolCoach. He is an alumnus of UC Berkeley and Harvard University, boasts degrees in Bioengineering, Molecular and Cell Biology, and a Ph.D. in Neuroscience. Ken previously worked with undergraduate students at Princeton Review where he was the only tutor certified in all subjects. Ken was one of the highest rated MCAT tutors ever and a teacher trainer. He founded Magoosh's MCAT division and has written content for dozen's of MCAT books and guides.

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How To Do MCAT Math Without A Calculator

• February 25, 2021
• Reviewed By: Liz Flagge

Is there math on the MCAT? Yup. Can you use a calculator on the MCAT? Nope. This scares a lot of students, but let’s think about it another way – although calculations may look tough initially, MCAT math is always subordinate to  science . The MCAT is not at all about math for the sake of math. You’ll be more than ready to tackle MCAT math problems on test day by doing practice and keeping these tips and tricks in mind. When you’re done, test your new skills with a  free MCAT practice test . 

MCAT Math Tips

First and foremost, you should be comfortable with working around units. Units are important because they help us keep track of what we’re using a number to qualify. Doing algebra with units is a way to check your work and to verify that you’re using the correct form of an equation. When taking the MCAT, you’ll likely have to pull at least a few equations from memory when answering a question, and it’s very normal to second-guess whether you’re putting the right variables in the right places, especially if the equation isn’t particularly intuitive. 

But what if we were dealing with  different  units of distance? For instance, what if there was a mismatch in scale, like if the question gave us information in meters, but all the answers were in millimeters? From the point of view of unit checking, as a way to make sure we’re putting the right variables in the right place of the equation, all we have to do is make sure the same TYPE of units end up in the same place on either side of the equation, without worrying so much about what those units are. In this case, as long as we see some unit for distance in the same place on both sides of the equation, we know that we’ve set up the problem correctly. However, when the time comes to match our units to the correct answer choices, we need to make sure that the specific units line up. 

This is where unit conversion comes in. To convert between units, we can utilize the concept of dimensional analysis. You might have seen this concept already, in the context of, say, stoichiometry, but it applies much more broadly to conversion between units in general. So, if we’re given an equivalence relationship between two units, like 1 foot equals 0.3 meters, we can write that as a fraction in the form of 1 foot divided by 0.3 meters or as 0.3 meters divided by 1 foot. Because 1 foot and 0.3 meters are equal, those fractions both equal 1, meaning that we can multiply any other value by that fraction without changing its magnitude. While doing so, we’re simultaneously doing algebra with the units, which results in them being changed. 

Choosing equations:

Remember that equations are tools, and we need to pick the right tool for the job. This means that the equation (or perhaps equations) should BOTH contain variables related to the information presented in the question stem AND yield a calculated result that corresponds to the answer choices. 

And here’s another possibility: what if the passage gives us a new equation related to frequency, perhaps in the setting of an experimental passage? Well, not to worry. The beautiful thing about passages is that no matter how involved or intimidating they seem, they  must  be accessible based on core MCAT content knowledge. Now, “accessible” doesn’t mean “easy”—the information you need might be buried in a blizzard of confusing terminology and acronyms—but the information does  have  to be there. This means that the key to handling novel equations is to leverage passage information to understand the point of the equation, and how it fits into the broader ideas discussed in the passage. Work through each variable in the equation one-by-one, making sure that you account for every variable. Even if you’ve never seen a certain symbol before, again, it must be defined somewhere. 

Calculation Errors to Look Out For:

●      Negative numbers 

Possibly the most classic example of a “silly math mistake” is obtaining an answer with the wrong sign – negative instead of positive, for instance. The best way to avoid this is to be very careful when subtracting a negative number. Subtracting a negative number is identical to adding the absolute value of that number; for instance, if I take 9 and subtract negative 6, this is the same as taking 9 plus 6 to equal 15.

This probably isn’t new to you, but it’s incredibly easy to forget to write down one of the negative signs, or simply to see “9,” “6,” and “minus” and think “3,” especially when plugging values into an equation that involves subtraction.

Likewise, care is needed when multiplying by negative numbers. In other words, if a minus sign is in the mix, it’s worth slowing down to make sure that everything lines up.

●      Dividing by a number less than 1

Another common source of mistakes is dividing by a number that is less than 1. Dividing any positive value by such a number must always result in a larger, or more positive, answer, while dividing any negative value by a number less than one will always yield a more negative answer. This can be a bit challenging to conceptualize; while 10 divided by 5 is quite obviously taking a group of 10 and dividing it into 5 smaller groups of 2, dividing 10 by 0.1 is a bit more abstract.

●      Failure to properly distribute when moving a term to the other side of the equation

Algebra errors are also quite common when manipulating equations. Most of these involve improper distribution when moving terms between the sides of an equation. As an example, take the kinematics equation vf2 = vi2 +2ad. Imagine that the only information we have is that acceleration is equal to -0.5m/s2, and that we’re trying to solve for displacement. First, we can plug in -0.5 for a, and multiply by 2 to give us vf 2= vi2 – d. Then, we subtract vi2 from both sides, yielding vf 2 – vi2 = d. Next up, we just need to divide both sides by negative 1 to get d isolated on the right side, but what  is  vf 2 – vi2 divided by negative 1? The most common mistake students make here is to only apply the negative sign to one of the terms on the left.

There’s no reason to freak out just because there is math on the MCAT. With some small additions to your MCAT prep, you can easily solve MCAT math problems without a calculator. Our  MCAT Self-Paced Course  and  MCAT Live Online  students have the option to attend supplemental office hours for more help with MCAT math. Blueprint MCAT free account students can register to attend  free MCAT webinars !

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The MCAT is essentially a science test, but you’ll still need a solid grasp of math fundamentals to score big —and you cannot use a calculator.

Our experts compiled a list of MCAT math topics to prep for along with some tips for doing math calculations by hand.

What math is covered on the MCAT?

The MCAT is primarily a conceptual exam, with little actual mathematical computation. Any math that is on the MCAT is fundamental: just arithmetic, algebra, and trigonometry. There is absolutely no calculus on the MCAT. Math-based problems will appear mostly in the Chemical and Physical Foundations of Biological Systems section . On the other science sections, a basic understanding of statistics as used in research will be helpful.

MCAT Math Tricks

1. practice for not having a calculator..

You aren’t allowed to use a calculator on the MCAT, so you need to practice doing arithmetic calculations by hand. Fortunately, the amount of calculation you’ll have to do is small. See how you score on our free MCAT practice test .

2. You only have to be reasonably accurate.

Try to make approximations so that you can do the math quickly. On the Chem/Phys section, your MCAT time per question is approximately 1.4 minutes (95 minutes for 67 questions). There simply isn't time for lengthy, complicated math!

Here's how it works. Which of the following calculations for figuring out the value of 23.6 × 72.5 is faster?

In the one-step calculation on the right, we approximated: 23.6 ≈ 25 and 72.5 ≈ 70. The answer we got in just a few seconds differs from the precise answer by only 2%. For the MCAT, you should always try to approximate so that you can do the math quickly.

Free MCAT Practice Tests & Events

Evaluate and improve your MCAT score.

3. Remember to pace yourself

If you find yourself writing out convoluted calculations on your scratch paper when you’re working through math-based MCAT problems, it’s important that you recognize that you’re not using your time efficiently. Say to yourself, “I’m wasting valuable time trying to get a precise answer, when I don’t need to be precise.”

4. Include some math review in your MCAT prep 

Are you rusty in any of these areas? You'll want to brush up on a few key math concepts during your MCAT prep .

Arithmetic, Algebra, Graphs

• Scientific notation, exponents, and radicals
• Fractions, ratios, and percents
• Equations and inequalities
• x-y  plane, lines, and other graphs

Trigonometry

• Pythagorean Theorem
• Sine, cosine, and tangent functions
• Sine and cosine values of common angles
• Inverse functions
• Radian measure
• Scalars and vectors
• Addition and subtraction of vectors
• Scalar multiplication
• Vector projections and components

Proportions

• Direct proportions
• Inverse proportions
• Laws of logarithms

Basic Statistics

• Mean, median, mode, range
• Standard deviation, normal distributions
• Variables, sample size, random samples, correlation
• Reliability, validity
• Randomized controlled trial, double-blind experiment

Research Methods

• Graphical analysis and interpretation
• Determining whether results are supported by data presented in figures
• Demonstrating an understanding of basic statistics and research methods
• Interpreting data presented in graphs, figures, and tables
• Drawing conclusions about data and methodology

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Everything You Need to Know to Master MCAT Math

Are you feeling overwhelmed by all the math required for the MCAT? Don’t worry; you’re not alone. In this post, we’ll get you ready for MCAT math questions you may see on exam day. So read on and get ready to ROCK MCAT Math!

How Important Is the MCAT Math?

There is no math section on the MCAT, rather, MCAT math will show up during the Chemical and Physical Foundations of the Biology section. This section tests your ability to solve problems and understand complicated concepts in a short time. MCAT Math is important because it is actually a good indicator of your readiness for medical school, it shows that you have the ability to handle the rigors of medical school. 

The key is to start studying early and use a variety of resources to get the best result. With some hard work and the right strategy, you can ace MCAT math and put yourself on the path to success in medical school.

Is the Math on the MCAT Difficult?

A lot of students get overwhelmed by the formulas and equations, but if you take a deep breath and remember that you’re smart enough to have gotten this far, you can do it! MCAT questions are all about problem-solving , so first, identify what the question is asking. Then, drop any answers that are clearly wrong. From there, it’s just a matter of plugging in your information and solving the equation. 

Remember, you have all the faculties to solve complex equations through critical thinking.

How to Prepare for Math on the MCAT

Take advantage of online resources like Jack Westin. At Jack Westin, we provide students with free resources to kick off their MCAT preparation. From our MCAT Diagnostic Exam , to our exhaustive Question Bank , we have all the resources you need to get started.

Second, make use of practice tests.These will help you identify areas that need improvement and focus your studying accordingly.

Third, identify your weaknesses. When it comes to mathematics, we all need some brushing up on algebraic equations, fractions, logarithms, and research statistics. Because of this, it’s important to understand where YOUR weaknesses lie. Is it, sine, cosine, and tangent functions, or scalar multiplication? By understanding your weaknesses you will be able to improve your skills faster and with more efficiency.

Finally, don’t forget to take breaks. Studying for the MCAT is intense, so make sure to give yourself time to relax and rejuvenate. Go for a walk, watch a movie, or just take some time to clear your mind. Breaks are essential for keeping your study sessions effective.

  Following these tips can make MCAT math studying more efficient and less daunting. 

Can You Use a Calculator on the MCAT?

If you’re planning to take the MCAT, you may be wondering if you can use a calculator on the MCAT. The answer is NO! Although MCAT Math is all about solving equations and using formulas, you can’t get help from a calculator and should rely on your own math skills. Plus, the MCAT doesn’t give you much time to solve each problem, so being able to quickly punch in numbers and get an answer can make a big difference. Just remember to practice without using your calculator before the test, so you wouldn’t be surprised on test day.

Strategies You’ll Need While Preparing for the MCAT Math.

MCAT Math can be tough – there’s no doubt about that. But there are some actionable strategies to help you solve math questions quickly and accurately:

• Make sure you understand the question . Read it carefully, and identify any keywords or concepts that will help you solve the equation. This will save you time and prevent frustration and help you get the answer right. So when you’re preparing for math on the MCAT, read the question carefully, and make sure you know exactly what the question is asking you. With this simple strategy, you’ll be well on your way to getting the score you want.
• Checking your work is one of the most important things you can do when preparing for the MCAT. Many candidates make the mistake of not checking their work, and as a result, they miss a lot of easy points. Always check your practice work after completing a practice exam. It’s a simple strategy that could make a big difference in your score.

  By following these steps, you’ll be able to approach math confidently and accurately.

The MCAT Math Concepts You Need to Know

So what are the most important MCAT Math concepts? Here are equations, formulas, and MCAT topic areas. Let’s take a look at each one.

Equations : There are a few different types of equations that you should know about, such as linear equations and quadratic equations. Familiarize yourself with these different types of equations so that you can confidently solve problems on the MCAT.

Formulas : Formulas are broken down into two parts: algebraic expressions and trigonometric functions. Algebraic expressions are used to solve problems involving variables, such as solving for x in an equation. 

Trigonometric Functions : Trigonometric functions are used in a variety of settings, from solving MCAT math problems to graphing the waveforms of sound waves. In many cases, they allow us to solve problems that would be otherwise impossible. For example, without trigonometric functions, we would be unable to calculate the height of a flagpole or the distance to a faraway object. We can also use trigonometric functions to find relationships between angles and sides in a triangle, which is helpful in fields like architecture and engineering.   

Here’s a breakdown of the mathematical concepts that you should review:

Arithmetic, Algebra, Graphs

• Scientific notation, exponents, and radicals
• Fractions, ratios, and percents
• Equations and inequalities
• x-y  plane, lines, and other graphs

Trigonometry

• Pythagorean Theorem
• Sine, cosine, and tangent functions
• Sine and cosine values of common angles
• Inverse functions
• Radian measure
• Scalars and vectors
• Addition and subtraction of vectors
• Scalar multiplication
• Vector projections and components

Proportions

• Direct proportions
• Inverse proportions
• Laws of logarithms

Basic Statistics

• Mean, median, mode, range
• Standard deviation, normal distributions
• Variables, sample size, random samples, correlation
• Reliability, validity
• Randomized controlled trial, double-blind experiment

Research Methods

• Graphical analysis and interpretation
• Determining whether results are supported by data presented in figures
• Demonstrating an understanding of basic statistics and research methods
• Interpreting data presented in graphs, figures, and tables
• Drawing conclusions about data and methodology

How to Save Time When Answering Questions

Significant figures .

In many cases, you can drop choices in the question by meaningful numerical calculations. However, if the possible answers are written in scientific notation, it is helpful to focus on the number of significant digits in the mantissa. Meaningful numbers indicate the reliability of the measurement based on the instrument. Therefore, the calculations need to take them into account. You can use the following rules to determine statistics. 

All numbers are significant between the first nonzero digit on the left and the last nonzero digit on the right. If the number contains decimal points, the zero to the right of the last non-zero digit is significant. If there are no decimals, these zeros are not significant. (For example, the number 4300.00 has 6 significant digits, while the number 4300 has 2 significant digits.) 

Leading zeros or zeroes before the first non-zero digit are not significant. (For example, the number 0.010 has two significant digits.) 

Also, special rules are required to perform calculations with significant figures. In addition and subtraction calculations, start by paying attention to the position of the leftmost decimal point. Calculate the problem from there and keep as many digits as possible until the calculation is finished. After getting this result, round the calculation result to the number of decimal places determined in the first step. 

The multiplication and division calculations first identify the factor, divisor, or dividend with the least significant digits. Then calculate the problem. Again, that number of digits is retained until the end. Finally, rounding the calculation results in the number of significant digits in the factor, divisor, or division determined in the first step.

Exponents are another way to eliminate possible answers. Since these are inverses of logarithmic functions, the exponential function follows a similar rule. 

If the answer choices are written in scientific notation, the radix of the exponent is always 10. You can check these radix 10 exponents to eliminate the choice of answering questions for very small or large sets. For example, if you are asking about the number of molecules contained in a few moles of a substance, you should expect a very large number. In this case, the answer is more likely to have an exponent of the 23rd power than the 5th power.

If you feel a little shaky about your math skills, don’t worry. We have plenty of opportunities to help you practice. Be sure to check out the Jack Westin Daily Questions for practice, or check out a Live Session . And if you want even more practice, try solving some real-world problems from the math section of the test. Good luck!

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NYT Connections today: See hints and answers for July 21

Connections is the latest New York Times word game that's captured the public's attention. The game is all about finding the "common threads between words." And just like Wordle , Connections resets after midnight and each new set of words gets trickier and trickier—so we've served up some hints and tips to get you over the hurdle.

If you just want to be told today's puzzle, you can jump to the end of this article for July 21's Connections solution. But if you'd rather solve it yourself, keep reading for some clues, tips, and strategies to assist you.

What is Connections ?

The NYT 's latest daily word game has become a social media hit. The Times credits associate puzzle editor Wyna Liu with helping to create the new word game and bringing it to the publications' Games section. Connections can be played on both web browsers and mobile devices and require players to group four words that share something in common.

Tweet may have been deleted

Each puzzle features 16 words and each grouping of words is split into four categories. These sets could comprise of anything from book titles, software, country names, etc. Even though multiple words will seem like they fit together, there's only one correct answer. If a player gets all four words in a set correct, those words are removed from the board. Guess wrong and it counts as a mistake—players get up to four mistakes until the game ends.

Players can also rearrange and shuffle the board to make spotting connections easier. Additionally, each group is color-coded with yellow being the easiest, followed by green, blue, and purple. Like Wordle, you can share the results with your friends on social media.

Here's a hint for today's Connections categories

Want a hit about the categories without being told the categories? Then give these a try:

Yellow: Political advocacy

Green: Physical condition

Blue: Things needed to build

Purple: Words found on a calculator

Here are today's Connections categories

Need a little extra help? Today's connections fall into the following categories:

Yellow: Ways to Support a Candidate

Green: Constitution

Blue: Carpentry Tools

Purple: Math Abbreviations

Looking for Wordle today? Here's the answer to today's Wordle .

Ready for the answers? This is your last chance to turn back and solve today's puzzle before we reveal the solutions.

Drumroll, please!

The solution to today's Connections #406 is...

What is the answer to Connections today

Ways to Support a Candidate : CAMPAIGN, CANVASS, ORGANIZE, STUMP

Constitution : COMPOSITION, FABRIC, MAKEUP, STRUCTURE

Carpentry Tools : CLAMP, FILE, LEVEL, SAW

Math Abbreviations : LOG, MAX, MOD, TAN

Don't feel down if you didn't manage to guess it this time. There will be new Connections for you to stretch your brain with tomorrow, and we'll be back again to guide you with more helpful hints.

Are you also playing NYT Strands? See hints and answers for today's Strands .

Is this not the Connections game you were looking for? Here are the hints and answers to yesterday's Connections .

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Topics Connections

KB5042421: CrowdStrike issue impacting Windows endpoints causing an 0x50 or 0x7E error message on a blue screen

Microsoft has identified an issue impacting Windows endpoints that are running the CrowdStrike Falcon agent. These endpoints might encounter error messages 0x50 or 0x7E on a blue screen and experience a continual restarting state.

We have received reports of successful recovery from some customers attempting multiple restart operations on affected Windows endpoints.

We are working with CrowdStrike to provide the most up-to-date information available on this issue. Please check back for updates on this ongoing issue. 

Important:  We have released a USB tool to help automate this manual repair process. For more information, see  New recovery tool to help with CrowdStrike issue impacting Windows devices .

To resolve this issue, follow these instructions for your version of Windows.

Hold the power button for 10 seconds to turn off your device and then press the power button again to turn on your device.

On the Windows sign-in screen, press and hold the  Shift key while you select  Power >  Restart .

Restart your device. Note  You may be asked to enter your  BitLocker recovery key . When the device restarts, continue pressing F4 and then it will log you in to safe mode. Please note, for some devices, you need to press F11 to log in through safe mode.

Once in safe mode, right-click Start , click  Run , type  cmd  in the Open box, and then click OK .

If your system drive is different than C:\, type C: and then press Enter . This will switch you to the C:\ drive.

Type the following command and then press Enter:

CD C:\Windows\System32\drivers\CrowdStrike

Note In this example, C is your system drive. This will change to the CrowdStrike directory.

Once in the CrowdStrike directory, locate the file matching “C-00000291*.sys”. To do this, type the following command and then press Enter :

dir C-00000291*.sys

Permanently delete the file(s) found. To do this, type the following command and then press Enter .

del C-00000291*.sys

Manually search for any files that match “C-00000291*.sys” and delete them.

Restart your device.

On the Windows sign-in screen, press and hold the  Shift  key while you select  Power   >  Restart .

Restart your device. Note  You may be asked to enter your  BitLocker recovery key .

When the device restarts, continue pressing F4 and then it will log you in to safe mode.

Once in safe mode, right-click Start , click  Run , type  cmd  in the Open box, and then click  OK .

Type in the following command and then press Enter :

Note  In this example C is your system drive. This will change to the CrowdStrike directory.

Recovery methods

If you receive the Windows Recovery screen, use one of the following methods to recover your device.

Method 1: Use Enable safe mode

Hold the power button for 10 seconds to turn off your device and thenpress the power button again to turn on your device.

On the Windows sign-in screen, press and hold the  Shift  key while you select  Power >   Restart .

After your device restarts to the  Choose an option  screen, select  Troubleshoot  >  Advanced options  >  Startup Settings  >  Enable safe mode . Then, restart your device. Note  You might be asked to enter your  BitLocker recovery key . When the device restarts, continue pressing F4 and then it will log you in to safe mode. Please note, for some devices, you need to press F11 to log in through safe mode.

If the screen asks for a BitLocker recovery key, use your phone and log on to  https://aka.ms/aadrecoverykey . Log on with your Email ID and domain account password to find the BitLocker recovery key associated with your device. To locate your BitLocker recovery key, click Manage Devices > View Bitlocker Keys > Show recovery key .

If your system drive is different than C:\, type C: and then press  Enter . This will switch you to the C:\ drive.

Type the following command and then press Enter :

Tip:  CD C:\Windows\System32\drivers\CrowdStrike

Note  In this example, C is your system drive. This will change to the CrowdStrike directory.

After your device restarts to the  Choose an option  screen, select  Troubleshoot  >  Advanced options  >  Startup Settings  >  Enable safe mode .  Then restart your device again. Note  You might be asked to enter your  BitLocker recovery key . When the device restarts, continue pressing F4 and then it will log you into safe mode. Please note, for some devices, you need to press F11 to log in through safe mode.

If the screen asks for a BitLocker recovery key, then use your phone and log on to  https://aka.ms/aadrecoverykey . Log on with your Email ID and domain account password to find the bit locker recovery key associated with your device. To locate your BitLocker recovery key, click Manage Devices > View Bitlocker Keys > Show recovery key .

Select the name of the device where you see the BitLocker prompt. In the expanded window, select View BitLocker Keys . Go back to your device and input the BitLocker key that you see on your phone or secondary device.

Note  In this example, C is your system drive. This will change to the CrowdStrike directory.

Method 2: Use System Restore

After your device restarts to the  Choose an option  screen, select  Troubleshoot  >  Advanced options  >  System Restore .

If the screen asks for a BitLocker recovery key, use your phone and log on to  https://aka.ms/aadrecoverykey . Login with your email id and domain account password to find the bit locker recovery key associated with your device. To locate your BitLocker recovery key, click Manage Devices > View Bitlocker Keys > Show recovery key .

Click Next  on System Restore.

Select the Restore option in the list, click  Next , and then click  Finish .

Click Yes  to confirm the restore. Note  This will perform just the Windows system restore and personal data should not be impacted. This process might take up to 15 minutes to complete.

If the screen asks for a BitLocker recovery key, use your phone and log on to  https://aka.ms/aadrecoverykey . Log in with your Email ID and domain account password to find the bit locker recovery key associated with your device. To locate your BitLocker recovery key, click Manage Devices > View Bitlocker Keys > Show recovery key .

Select the Restore option in the list, click Next , and then click  Finish .​​​​​​​

Contact CrowdStrike

If after following the above steps, if you still experience issues logging into your device, please reach out to CrowdStrike for additional assistance.

Start your PC in safe mode in Windows

Third-party information disclaimer

The third-party products that this article discusses are manufactured by companies that are independent of Microsoft. We make no warranty, implied or otherwise, about the performance or reliability of these products.

We provide third-party contact information to help you find technical support. This contact information may change without notice. We do not guarantee the accuracy of this third-party contact information.

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CrowdStrike Outage: How to Fix Your Windows PC With the Blue Screen of Death

If the CrowdStrike software bug is still affecting your Windows computer, there's a fix.

The CrowdStrike crash only affects Windows, not Mac or Linux.

The worst of it may finally be over, but some people are still dealing with the CrowdStrike chaos.

Last Thursday's event, a Microsoft outage  that crippled airlines and financial, health-care and energy companies across the world, resulted for many in a "blue screen of death" on their work computers. In response, Microsoft on Saturday released a recovery tool to help repair Windows machines affected by the bug, a day after CrowdStrike provided instructions for how to fix a crashed PC.

CrowdStrike, a cybersecurity firm whose software protects small businesses and large companies from cyberattacks and other online threats, said it caused the outage when it sent out a software update containing a glitch, crashing Windows computers running the company's software. The bug does not affect Mac and Linux computers. 

"We understand the gravity of this situation and are deeply sorry for the inconvenience and disruption," the company said in a statement. 

The fallout was massive. Airport travelers were stranded. Hospital appointments have been delayed or canceled. And some employees are still unable to get work done, all because of this software update, which has caused the infamous blue screen of death on Windows PCs with the CrowdStrike glitch.

On LinkedIn on Monday, CrowdStrike posted , "Of the approximately 8.5 million Windows devices that were impacted, a significant number are back online and operational." However, if you're still dealing with the blue screen of death on your PC, there is a fix, which CrowdStrike itself has posted on its website.

If you see this, it means your system crashed.

How to fix your Microsoft Windows PC impacted by the CrowdStrike bug

Microsoft on Saturday released on its Microsoft Download Center  a USB tool that it said can help IT administrators with the repair process. The tool requires you to have administrative privileges and a BitLocker recovery key for each Windows PC. Microsoft also posted recovery steps to fix PCs continually restarting because of the faulty CrowdStrike update.

On Friday, CrowdStrike said it has identified the issue and has sent out a fix. "We refer customers to the support portal for the latest updates and will continue to provide complete and continuous updates on our website."

The first thing you should try to solve the blue screen of death is to  restart your Windows computer until CrowdStrike's fix comes through . CrowdStrike CEO George Kurtz on Friday appeared on NBC's "Today" show and said "Many of the customers are rebooting the system and it's coming up operational because we fixed it on our end."

This has in fact worked for many people.  This user on X had success after rebooting their computers several times. Microsoft has also said that it's received feedback that doing several reboots (as many as 15) has been effective.

However, if you're still having issues  even after rebooting, CrowdStrike recommends booting up into safe mode and then deleting the corrupted file. This is what the company details on the CrowdStrike website:

• Boot your Windows computer into Safe Mode or the Windows Recovery Environment.
• Navigate to the %WINDIR%\System32\drivers\CrowdStrike directory.
• Locate the file matching "C-00000291*.sys" and delete it.
• Boot the host normally.

Note : Bitlocker-encrypted hosts may require a recovery key.

If you're dealing with a public cloud or another virtual environment, there's a different fix for you that CrowdStrike recommends, which you can check out over at its website . 

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EXCLUSIVE: Elon Musk’s transgender daughter says he berated her as a child for being queer

What we know about the global Microsoft outage

A routine software update caused cascading chaos Friday that has engulfed global businesses from airports and banks to retail and law enforcement.

It wasn’t a cyberattack, but was caused by one of the world’s largest cybersecurity companies deploying a flawed update while trying to keep their customers safe from hackers.

CrowdStrike, a cybersecurity company based in Austin, Texas, that’s widely used by businesses and government agencies that run on Microsoft computers, said that a defect in one of its updates for computers running the Windows operating system had caused the issue. The result was arguably the largest global information technology outage in history. 

Here’s what we know:

What has been affected?

The outage appeared to affect almost every major business sector in one way or another.

Airports and flights across the world were severely delayed or canceled altogether, as the computers on which these services rely were disrupted by the issue. Three of the largest airlines in the United States — American Airlines, Delta Air Lines and United Airlines — all issued ground stops, citing communications problems.

Long lines snaked through airports from Berlin to Hong Kong, as electronic systems failed and staff members resorted to checking in passengers manually. One flier in the Indian city of Hyderabad posted a picture of a curiosity usually unseen in the modern digital age: a handwritten boarding pass.

Follow live updates on the global tech outage

The issue also affected banks, leaving some customers unable to access their money. People across Australia, New Zealand and elsewhere reported problems logging into their accounts at major retail banks. Meanwhile the London Stock Exchange, the largest of its kind in Europe, said some of its services had been disrupted although trading had not been impeded.

In retail, McDonald’s closed some of its stores in Japan because of what it said in an online statement was a “cash register malfunction.” And the British grocery chain Waitrose was forced to put up handwritten notes informing customers that it was only accepting cash. Some Starbucks locations temporarily closed after the company's mobile ordering system went down, while other locations stayed open and left their baristas scrambling to come up with new workflows.

Baltic Hub, a global shipping terminal in Poland, said in a statement it had been battling issues related to the outage. The Alaska State Troopers agency was among the law enforcement agencies to report issues, warning people that 911 was temporarily not working. And the British broadcaster Sky News, which is owned by NBCUniversal's parent company, Comcast, was briefly knocked off the air.

Some computers that were not on during the software update appear to have avoided the issue, according to initial reports.

What caused it?

Cybersecurity programs like CrowdStrike’s frequently and automatically update themselves to account for new tactics that malicious hackers have discovered. And there’s always a slight risk that any software update will be incompatible with other programs.

CrowdStrike’s update should have been routine, but an error in its code conflicted with Windows and proved catastrophic.

The company’s CEO, George Kurtz , said Friday morning on the "TODAY" show that while some customers would see their computers fixed automatically, others would require manual work to fix.

“The system was sent an update, and that update had a software bug in it and caused an issue with the Microsoft operating system,” Kurtz said. “Our systems are always looking for the latest attacks from these adversaries that are out there.”

How long until things go back to normal?

CrowdStrike identified the problem and issued a fix early Friday after the problem began to emerge. On Friday afternoon, Kurtz released a statement apologizing for the outage, adding that CrowdStrike was “operating normally.”

The fix required affected computers to download another software update, which some have been able to do automatically.

Many companies and services affected by the chaos, such as the New Hampshire Department of Safety, which said its 911 system was briefly down, reported that they were back online by Friday morning. 

Others haven’t been able to load the update, which would potentially require IT workers at some companies to reboot and tinker with every single affected computer.

“Many of the customers are rebooting the system, and it’s coming up, and it’ll be operational because we fixed it on our end,” Kurtz said. “Some of the systems that aren’t recovering, we’re working with them. So it could be some time for some systems that just automatically won’t recover.”

Alexander Smith is a senior reporter for NBC News Digital based in London.

Kevin Collier is a reporter covering cybersecurity, privacy and technology policy for NBC News.

Saks Fifth Avenue in San Francisco will require all shoppers make an appointment. The controversial move could solve a major headache.

• Saks Fifth Avenue is rolling out its appointment-only system at its San Francisco location.
• The luxury retailer has opened a dozen other "Club" concepts across the US in the past year.
• Retail analyst Neil Saunders told BI that requiring appointments will likely help prevent shoplifting.

Saks Fifth Avenue shoppers visiting the brand's San Francisco store may need something they previously haven't: a reservation.

The retailer said last week it will convert its Union Square location from a traditional department store format to an appointment-only concept, beginning on August 28.

Saks has opened roughly a dozen similar — but much smaller — "Club" concepts across the US in the past year, usually on-site at hotels and resorts. Saks currently has two such Clubs near San Francisco: one in Napa, and one in Palo Alto.

"We're always looking for innovative ways to optimize our store experience to match luxury consumers' evolving expectations, including by meeting our customers where and how they want to shop with us," a company spokesperson said in an email to Business Insider about the change.

Saks President Larry Bruce previously touted the success of the new concept in an announcement last month about the expansion of new locations.

"The success of our standalone Fifth Avenue Club suites illustrates that luxury clients are increasingly seeking one-on-one fashion expertise tailored just for them," he said. "We are proud to have cultivated a new, engaged client base and a skilled stylist team that delivers one-of-a-kind personal shopping and styling tailored to the unique lifestyles of our customers within each community."

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Saks is by no means the first high-end retailer to focus on more personalized service, especially for wealthy clients.

"Certain luxury department-store locations like the Neiman Marcus in Las Vegas operate by appointment only," Amanda Lai, a director at consultant McMillanDoolittle, told CoStar . "Appointment-only stores have become a growing trend among luxury fashion houses, and locations like the Gucci Salon in L.A. and Brunello Cucinelli store in New York have opened up to serve ultra-high-net-worth clientele in a discrete, upscale setting."

These appointment-only stores also require fewer staff, and the San Francisco Chronicle reported that the company will lay off an unspecified number of workers.

Still, a full-size department store is far larger than a suite in a hotel, but there are a few likely reasons why Saks would be interested in trying to scale up the boutique concept.

Just as Union Square is a major center of retail in San Francisco, it has also been a statistical epicenter of retail crime .

The company did not address BI's question about whether retail crime factored into the decision to convert the store, but retail analyst Neil Saunders said requiring appointments will likely prevent shoplifting.

"This move is essentially about Saks trying to make the San Francisco store work better," Saunders told BI. "A store that operates by appointment only can get away with far fewer staff. It is also a way of preventing theft."

In addition, one unnamed source told the Chronicle the shift was probably due to the area's "challenging" environment for retailers.

Even as crime rates fall , foot traffic in the area has fallen too, creating additional headaches for brands such as Macy's and Nordstrom, both of whom left the area.

"This only works because Saks likely has customers that spend very high amounts in a single transaction," Saunders told BI. "This kind of model would not work for mass market retailers."

Meanwhile, ultra-luxury brands are maintaining a presence near Union Square, with watchmaker Breitling spending some $1 million to renovate a space that situates it near shops for A. Lange & Söhne, Patek Philippe, and Rolex.

The San Francisco Standard spoke with several shoppers in the area who expressed disappointment at Saks becoming less accessible to regular people.

"Some shopping should feel like it has a bit of spontaneity," Natali Bagamyan, a tourist from Switzerland, told the Standard. "If I need to have an appointment, I won't do it. It's a bit of a buzzkill."

But that may not be much of a concern for luxury consumers who, as BI's Emily Stewart writes, are still showing a strong preference for in-person retail experiences : "They don't just want to buy something special — they want to be treated special while they do it."

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