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Posted on
17
Sep 2020

Which Is The Greatest – GMAT Problem

Today we’re going to look at a GMAT problem that screams for estimation but can really tie you in knots if you don’t have the right pivot question, the right perspective. Of the following which is greatest? And on its surface this would seem like a straightforward question except of course the GMAT being the GMAT they’re going to give you a bunch of numbers that are going to be hard to interpret. One part of this problem is simply training. The square root of 2, the square root of 3, the square root of 5. These are common, especially root 2 and root 3 because we see them a lot on triangle problems.

Get Familiar With Identities

And knowing these identities by heart as an estimate is really, really valuable just for being able to get a bearing whether you’re on a geometry problem and you’re trying to navigate or make sure that your answer seems correct or if you’re in a problem like this knowing these identities root 2 is 1.4, root 3 is 1.7, root 5 is 2.2 is useful as a touchstone.

Break Down The Problem

But this problem in general and the greater problem can be broken down not by saying oh well this is 1.4, this is 1.7, but by asking ourselves well logically which is bigger which is smaller. Remember it’s a multiple choice exam and they’re asking for the biggest or the smallest or whatever it is but these are opportunities to compare not nail down knowledge and this attitude is exceptionally vital for the data sufficiency but it crops up in problem solving a lot more than people might care to admit.

Especially if you’ve been there just trying to study and study and study and get to a precise answer on a lot of these things. So, let’s start just by taking a look at a few things. First square root of three square, root of two which one’s larger? If you said root three you are correct. How much larger? That might be a little bit more difficult to ascertain but if you say 1.7 versus 1.4 maybe 20 percent larger 3 is 50% larger than 2 so root 3 is going to be some smaller percentage larger than root two. But either way we know that root three is the bigger one it’s going to be the dominant value so the question becomes how much larger? Or which part of the answer drives the answer choice?

What Do We Know?

So we know that the integers 2 and 3 are more meaningful, larger than the square roots because the square roots are components of those integers. So between A and B, a drives the question that is the three drives the root two more than the two drives the root three. We can take a look at the following two and notice that both of them are around root three.

That is if we take apart the ugly part, which is the square root and take a look at the rest of it – four over five, five over four, these numbers are about one and compared to the two root three we have and the three root two which we’ve already decided is even stronger we don’t really need to entertain C and D all that much. Just to understand that oh they’re about a root three and that’s not going to be enough.

Looking At Answer Choice E

Finally, we have E. E is a little funky but we can ask ourselves how many times will root 3, will this 1.7 go into 7 and we get this answer that it’s a bit below 4. Compared with 3 root 2 which is 4.2 (3 times 1.4), we still have a driving the answer. You guys see how this is a marriage of doing a little bit of estimation but also really keeping your framing as is this greater or less than. Now we’ve included a bunch of other different answer choices here for you to take a look at play around with it and see if you can get yourself familiar with comparing these things because the GMAT is only going to come at you with things like square roots that are unfamiliar.

So it’s a fairly defined GMAT problem in that sense. I hope this helps, questions below, like us, subscribe, keep checking in and we’ll see you again real soon.

If you enjoyed this GMAT problem, try these problems next: Probability problem, and the Speed Distance problem.

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Posted on
06
Aug 2020

Probability GMAT Problem

Probability GMAT Problems can be super complex if you don’t frame it correctly. One of the keys to looking at probability problems, particularly conditional probability and independent probability problems, is breaking each part up into its own entity, and a lot of times this clarifies the problem.

Introduction To The XYZ Probability Problem

Let’s take a look at this ‘XYZ’ probability problem. Xavier, Yvonne, and Zelda are solving problems. We’re given the 3 probabilities for correct answers and we’re being asked what’s the probability of X being right and solving it, Y solving it, and Z not solving it.

The first thing we can look at is, say: “Well what’s the probability of Zelda not solving it?” And it’s just going to be the flip, the other side of 5/8 to bring us up to 1. If she solves it 5 out of 8 times, she’s not going to solve it the other 3 out of 8 times. So, we’re dealing with 1/4, 1/2, and 3/8.

Doing The Math May Seem Simple

The math here is straightforward, multiply them together. But that might not be readily apparent, or at the very least, just plugging it into that formula can get you into trouble. So, here’s where owning it conceptually and mapping it out with a visualization helps you take command of this problem. 

Xavier Getting It Correct

Since each probability is independent of the others we can look at them independently. What’s the probability of Xavier getting this correct? 1 out of 4 times. So, we can say in general, for every four attempts, he gets it correct once or 25%. If, and only if Xavier gets it correct can we move on to the next part – Yvonne.

Yvonne Getting It Correct

Xavier gets a correct 1 out 4 times then what are the chances that Yvonne gets a correct? 1 out of 2. So to have Xavier get it correct and then Yvonne get it correct it’s going to be 1 out of 8 times – 1/4 times 1/2.

It’s not that we can’t look at a Yvonne when Xavier gets it incorrect, it’s that it doesn’t matter. From a framing perspective, this is all about only looking at the probability for the outcome that we want and ignoring the rest.

Zelda Getting It Incorrect

Xavier: 1 out of 4, Yvonne: 1 out of 2, gets us to 1 out of 8. Then and only then, what are the chances that Zelda gets it incorrect? 1 out of 8 trials brings us to X and Y are correct, then we multiply it by the 3/8 that Zelda gets it incorrect. That gets us to 3/64. 3 out of every 64 attempts will end in ‘correct’, ‘correct’, ‘incorrect’.

This is one of those problems that may have to go through a few times but once you attach the explanation to it, you can’t mess up the math.

If you enjoyed this GMAT probability problem, try your hand at these other types of challenging problems: Combinatorics & Algebra

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GMAT test strategies
Posted on
09
Jul 2020

8 GMAT Test Strategies To Help Boost Your Score

by ApexGMAT

Contributor: Ivan Minchev

June 22st, 2020

More than 250,000 students take the GMAT every year as a requirement to get into the thousands of different MBA, EMBA, MFin, MAcct and Management PhD programs worldwide. However, due to the complexity of the exam as well as its adaptive difficulty only the top 12% of test-takers manage to score 700 or above. Here are 8 GMAT test strategies you can utilize to achieve a higher score on the exam, no matter where you currently are on your GMAT preparation journey.

1. Adopting the proper mindset

Perspective  is everything. It is very important to understand that even though getting in the top 10% of test-takers might seem like a spectacular achievement (and don’t get me wrong, it certainly is) setting your goals on a certain score tends to be counterproductive. Instead, focus on attaining specific skills, knowledge, and command, and the score will follow. Goals lead to expectations and fear of failure, and fear of failure in turn results in stress, which can greatly hinder performance.

2. Overcoming stress!

Stress and fear can greatly influence your results, but there are ways to manage these very normal responses to a high stakes situation. One of the ways to reduce stress and boost your confidence is by beginning your preparation process as early as possible – ideally 90-120 days before the exam. This provides enough time to fully grasp the complexities of the exam, and more importantly internalize a new set of skills to handle that complexity.

A test taker’s greatest enemy is test anxiety. Understand that anxiety happens to everyone. What sets top performers apart is how they handle that anxiety, and how they direct it back into their performance. Many people use a variety of relaxation techniques for dealing with test anxiety. The most common and easy to use method is to practice deep and controlled breathing in combination with visualization techniques. 

3. For exam day…

Are you a coffee drinker? Surprisingly, caffeine can really help your performance on test day. Caffeine is a powerful nootropic that will help keep your senses sharp and will also boost the oxygenated blood flow to your brain, subsequently enhancing your performance. For more info on how coffee affects your performance click here

Remember how we said that it’s important to begin your exam prep early? This “early bird” attitude can be applied in more ways than one. What this implies is that you must (not might, not should) prepare your GMAT Test Day Survival Kit on the previous day and not leave this for the last moment. Everyone has waited for the last minute to do something, and chances are everyone has left something crucial behind. With the GMAT being such an important exam such situations should be avoided as much as possible. Try having a mock exam day. Map out the whole test day and practice it as if it were real, including your trip to the testing center. This will help you normalize the process and alleviate anxiety on test day.

4. Value your time and manage it efficiently!

Since the GMAT is a timed exam one’s planning and strategic skills are put to the test as they have to come up with an efficient time management strategy.

Use mental math tools whenever possible and also try getting used to reading and analyzing charts, graphs and tables efficiently for the Integrated Reasoning section. 

Once you’re further along in your preparation and have mastered seeing multiple solution paths before engaging any of them, familiarize yourself with common problems, and built up test reading and perspective skills, then you can begin dedicating yourself to timed sets: working on a cluster of 10 consecutive questions for each section of the exam when on the clock. This helps you calibrate your timing decisions and more readily notice when they require adjustment.

Remember, just because the GMAT is a timed exam, this doesn’t mean we must learn under a time constraint. Like good cooking, good learning takes time. Give yourself sufficient time to learn, while also making sure the learning time is spent as productively as possible.

5. The Integrated Reasoning section

Dealing with 12 multi-part questions in 30 minutes means that you’re going to be overwhelmed with information, and you won’t have much time to spare. Sorting through large amounts of data and understanding it in a timely manner is key to getting through this section.

A good way to rapidly identify information needed to solve a problem is knowing what to look for. Read the problems carefully (and this applies to all sections) and proactively determine what you want out of the information or solution path. This way, you will sift out most unnecessary information in advance, saving plenty of time along the way. However, this does NOT mean to ignore the text written around the tables/graphs/charts.

6. The Analytical Writing section 

Failing to plan is planning to fail! Always plan your essay! Set aside 4-5 minutes to plan what you are going to write and how you are going to structure your essay. 

Create an essay template in advance! There are many ways you can go about making one but usually, the more you practice your essay writing skills the more used to a specific writing style you are going to get ultimately resulting in your own template.

7. Ask for help

There is nothing embarrassing about asking for help, especially when it comes to an exam that is so vital to one’s future. There are numerous GMAT forums and courses on the web, where you can ask and get help from people who have already taken it.

However, if you would prefer a more personal and individualized approach you could consider hiring a private tutor. The benefit of not preparing alone but hiring a tutor is that it allows for direct feedback on what are an individual’s strengths and what needs improvement, while also receiving advice on how to achieve those improvements. As a result, when the exam day comes you will not only be well prepared but will also know it, having built up confidence in your abilities.

8. Practice, practice, practice!

No doubt you’re familiar with the phrase “practice makes perfect.” There is a reason why this is such a popular saying: it’s true! Not all practice is equal, though. Varied practice that aims at building on existing skills and knowledge is much more high yielding than repetition. No matter how clever you are, no matter how good of a student you’ve been or how proficient in math you are if you do not put enough time and effort in your prep you are not likely to be happy with the end result. Even the top tutors and courses out there won’t be able to help you out if you don’t give your best. So remember, don’t just go through the motions, but practice by constantly looking at the same problems and concepts in new ways, and trying to use them in novel situations, and you’ll find your GMAT prep vastly accelerated.

That was the list of 8 strategies to help you score high on the GMAT. Keep in mind that what works for one person will not necessarily work for another as everybody learns differently. It is only through practice and proactive learning that you will be able to find what are the best methods for your success. 

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Posted on
07
Jul 2020

GMAT Problem – Speed Distance Problem

Speed and distance problems are among the most complained about problems on the GMAT. Numerous clients come to us and say they have difficulty with speed and distance problems, word problems, or work rate problems. So we’re going to look at a particularly difficult one and see just how easy it can be with the right approach.

The Two Cars Problem

In this problem we have two cars – car ‘A’ and ‘B’. Car ‘A’ begins 20 miles behind car ‘B’ and needs to catch up. Our immediate DSM (Default Solving Mechanism) is to dive in and create an equation for this and that’s exactly what we don’t want to do.

These types of problems are notorious for being algebraically complex, while conceptually simple. If you hold on to the algebra, rather than getting rid of it, you’re going to have a hard time.

Solution Paths

In this problem we’re going to build up solution paths. We’re gonna skip the algebra entirely. We’re going to take a look at an iterative way to get to the answer and then do a conceptual scenario, where we literally put ourselves in the driver’s seat to understand how this problem works. So if we want to take the iterative process we can simply drive the process hour-by-hour until we get to the answer.

Iterative solution path

We can imagine this on a number line or just do it in a chart with numbers. ‘A’ starts 20 miles behind ‘B’ so let’s say ‘A’ starts at mile marker zero. ‘B’ starts at 20. After one hour ‘A’ is at 58, ‘B’ is at 70 and the differential is now -12 and not -20. After the second hour ‘A’ is at 116, ‘B’ is at 120. ‘A’ is just four behind ‘B’. After the third hour ‘A’ has caught up! Now it’s 4 miles ahead. At the fourth hour it’s not only caught up but it’s actually +12, so we’ve gone too far. We can see that the correct answer is between three and four and our answer is three and a half.

Now let’s take a look at this at a higher level. If we take a look at what we’ve just done we can notice a pattern with the catching up: -20 to -12 to -4 to +4. We’re catching up by 8 miles per hour. And if you’re self-prepping and don’t know what to do with this information, this is exactly the pattern that you want to hinge on in order to find a better solution path.

You can also observe (and this is how you want to do it on the exam) that if ‘A’ is going 8 miles an hour faster than ‘B’, then it’s catching up by 8 miles per hour. What we care about here is the rate of catching up, not the actual speed. The 50 and 58 are no different than 20 and 28 or a million and a million and eight. That is, the speed doesn’t matter. Only the relative distance between the cars and that it changes at 8 miles per hour.

Now the question becomes starkly simple. We want to catch up 20 miles and then exceed 8 miles, so we want to have a 28 mile shift and we’re doing so at 8 miles an hour. 28 divided by 8 is 3.5.

Conceptual scenario solution path

You might ask yourself what to do if you are unable to see those details. The hallmark of good scenarios is making them personal. Imagine you’re driving and your friend is in the car in front of you. He’s 20 miles away. You guys are both driving and you’re trying to catch up. If you drive at the same speed as him you’re never going to get there. If you drive one mile per hour faster than him you’ll catch up by a mile each hour. It would take you 20 hours to catch up. This framework of imagining yourself driving and your friend in the other car, or even two people walking down the street, is all it takes to demystify this problem. Make it personal and the scenarios will take you there.

Thanks for the time! For other solutions to GMAT problems and general advice for the exam check out the links below. Hope this helped and good luck!

Found it helpful? Try your hand at some other GMAT problems: Profit & Loss Problem.


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Posted on
11
Jun 2020

Snack Shop GMAT Problem

The Snack shop GMAT problem is an average or a mean problem. A characteristic of many average problems is that one big takeaway right at the outset is that the answer choices are clustered tightly together. We want to refrain from making any calculations.

The problem is below:

snack shop problem

Selecting A Solution Path

If they’re looking for a level of precision, the estimation solution path isn’t available to us. If we dive into the problem, right from the first sentence we have sort of a conclusion that we can create via either a graphic or accounting solution path.

If you were the business owner immediately you’d say to yourself: Well for 10 days and an average of $400 a day I made $4000. 

This is how we want to think about averages. Many times they’ll tell us a parameter about a length of time or over a certain universe of instances and here we want to treat them all as equal.

Solving the Problem

It doesn’t matter if one day we made 420 and another day we made 380. We can treat them in aggregate as all equal and start out with that assumption. That’s a very useful assumption to make on average problems. So, we start out knowing that we made 4,000. 

What I want us to do is do a little pivot and notice from a running count standpoint how much above or below we are on a given day. So we’re told that for the first six days we averaged $360 which means each of those six days we’re short $40 from our average. That means in aggregate we’re short $240. 6 days times $40 –  and this has to be made up in the last 4 days.

Notice how we’re driving this problem with the story rather than with an equation. In the last four days we need to outperform our 400 by 240. 240 divided by 4 is 60. 60 on top of the 400 target 

that we already have is 460. Therefore, our answer is D.

Graphical Solution Path

If we are more comfortable with graphic solution paths, imagine this in terms of 10 bars each representing $400. Lowering six of those bars down by 40 and taking the amount that we push those first six down and distributing it among the last four bars gives us our $460 total per day.

snack shop graphic solution path

If you enjoyed this Snack Shop GMAT Problem, watch “The Gas Mileage GMAT Problem” next.

 

 

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Posted on
28
May 2020

Gas Mileage GMAT Problem

The Gas Mileage problem is a classic example of the GMAT triggering one of our DSM’s: Our Default Solving Mechanisms for applied math. Yet there are three higher level solution paths that we can engage instead. So we are going to skip the math entirely on this one. In reading the question stimulus, there’s a signal that estimation is going to be a very strong and viable solution path and in fact for most folks estimation is the dominant solution path for this problem.

What to Take Note Of

Notice in the first sentence here that we are given the relationship between the efficiency for Car X and the efficiency for Car Y. When comparing 25 to 11.9, 11.9 is a little bit less than half. Whenever we have a relationship that is a little less or a little more than a factor, that’s a clear signal that the GMAT wants us to estimate.

Now, we have an inverse relationship here, between the efficiency of Cars X and Y and the amount of gas they use. So if Car Y is using a little half or rather if Car Y has a little less than half efficiency it’s going to use a little more than double the amount of gas. Managing the directionality of estimation is essential to make full use of this solution path.

Estimation Solution Path

Right off the bat, we have a sense that Car Y is going to use a little bit more than double the amount of gas. Now, all we need to do is figure out how much Car X will use. This is an exercise in mental math. Instead of dividing the 12,000 miles by 25 we want to build up from the 25 to 12,000.

Ask ourselves, in a scenario type of way, how many 25’s go into 100 – The answer is 4. 4 quarters to a $1. Then we can scale it up just by throwing some zeros on. So, 40 25’s are 1,000. How do we get from 1,000 to 12,000? We multiply by 12. So 40 times 12, 480 25’s gives us our 12,000 miles. Car X uses 480 gallons.

Therefore, Car Y is going to use a little more than double this and we point to answer C because we just need to answer the amount Y uses in addition to X. SO there is a bit of verbal play there that we also have to recognize. That’s the estimation solution path.

Graphical Solution Path

We can see this via the graphic solution path by imaging a rectangle, where we have the efficiency of the engine on one side and the amount of gallons on the other. With Car X, 25 miles per gallon time 480 gallons is going to give us the area of 12,000 miles. That is we’ve driven the 12,000 miles in that rectangle. If we are cutting it in half on efficiency, or a little more than half, we end up with two strips and if we lay them side by side we see that we’re doubling of going a little more than double on the amount of gas that we use to maintain that 12,000 mile area.

Logical Solution Path

Finally, we can look at this from a logical solution path which overlaps a bit with the estimation. But the moment we know that Y uses a little more than double the amount of gas of X, we can also look at and not manage that directionality and just say it uses about double. The only answer choice among our answer choices that is close but not exactly, is C – 520. 480 is our exact number and the A answer is way too low. It’s not close enough to 480 to be viable. So here is an example where, while best practices have us managing the directionality, we don’t even need to do that.

Similar Problems

For similar problems like this take a look at the Wholesale Tool problem, The Glucose Solution Problem and for a really good treatment of the graphic solution path check out Don’s Repair Job. There should be links to all three right below and I hope that this helps you guys on your way to achieving success on the GMAT.

If you enjoyed this Gas Mileage Problem but would like to watch more videos about Meta strategy, try “How coffee affects your GMAT performance“.

 

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Posted on
19
May 2020

GMAT Scoring – Demystified

One of the most common questions asked by those who are new to the GMAT is how exactly does the computer adaptive test or CAT work? The long and short of it is that if you get a problem correct, they give you a harder one, if you get a problem incorrect, they give you an easier one. By doing this the GMAT is able to bounce up and down and calibrate to your skill level.

Should You Spend more time on the first 10 questions?

A few things come out of this including questions about how to spend your time. Whether certain questions are weighted more than others, whether your timing, that is the amount of time you spend on a problem factors into the score.

To start, there’s a common misconception that you should spend more time on the first 10 questions because they tend to adjust your level for the computer adaptive test at a greater rate. While that’s true in the sense that the computer adapted model on the GMAT does influence it more at the outset, whether you should spend more time is actually a more complex question because generally the GMAT is going to give you problems that are about average and build up or down from that average.

Planning To Score An Elite GMAT Score

If you’re planning on performing at a top level, at an elite level, if your goal is 700 or even 600, you need to assume that those early problems that are average level problems you’re going to do well and in a timely manner anyway.

That is spending extra time to ensure you get them correct is a grandiose version of spending extra time to make sure that you’re getting two plus two correct. You wouldn’t check that because you’re confident enough in your skills and if you’re in the GMAT and you’re getting ready to shoot for a 700 you should already be confident enough in your skills not to have to spend extra time on average level problems. To take these problems on a problem-by-problem basis rather than with blanket statements.

Does The Test keep Track of Other Information?

A common question is whether or not the test keeps track of the type of problems you do. This can refer to:

    • subject matter
    • problem solving versus data sufficiency 
    • reading comprehension versus critical reasoning versus sentence correction

However, we can still go about it with the core rule: if you get it right you’re going to see something more challenging, get it wrong, less challenging. We tend to believe that they don’t keep a great track of that but really rely upon the bouncing up and down to calibrate you to your average performance level. You don’t want to sweat any single problem or worry about any single problem type in regards to the Computer Adaptive Test.

Certainly,  sometimes you’ll know that certain types of problems require more or less attention from you or that you make common errors on those problems. However, that’s not a CAT thing, that’s just a general GMAT thing. 

You are penalized for spending too much time on a problem but not in the way you think.

The other big question we hear a lot is whether or not the amount of time you take on a problem factors into the score. The answer here is subtle, it’s yes and no. No in the sense that the GMAT scoring algorithm does not track the amount of time that you spend on a problem. But, yes in the sense that the more time you spend on problems the less time you have for other problems. In particular, if you’re scoring above average, you’re on this ascendant curve so that the difficult problems at the end require more time than the less challenging problems at the beginning.

Therefore, if the GMAT kept track of your time and penalized you for spending longer on problems they would actually be penalizing you twice and this gets us into our timing decisions and the trade-off between time and score.

Time and Score Trade-off

When you’re armed with confidence and knowledge about how something works you don’t have to worry about how it works or how what you’re doing affects how it works and you can focus on the task at hand. 

The more that you can offload the burden of worrying about the scoring and the mechanisms by which the GMAT measures you, the more success you will find. As always, I hope this helps and keep prepping!

If you enjoyed GMAT Scoring Demystified, watch The Effects Of Coffee On GMAT Performance.

 

 

 

 

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Posted on
14
May 2020

The Effects of Coffee on GMAT Performance

Let’s talk about caffeine and the effect of coffee on GMAT performance. Caffeine is a neuro-stimulant. Drinking coffee or tea while you prep and particularly being appropriately caffeinated when your test is a decided advantage. Caffeine is a nootropic, which means it helps you be smarter. It also helps your cognitive abilities become enhanced due to increased blood flow and oxygen flow to the brain.

Find Your Right Amount

It’s important to understand how much caffeine helps, not just to wake you up in the morning. More than that, it’s about how much caffeine is needed to get you to that a really nice steady state of alert focus-ness (where you’re making up words like alert focus-ness) where you kind of feel on top of the world and you have that gentle energy.

You want to understand exactly how much caffeine your body can take because there’s nothing worse than being over caffeinated, jittery and anxiety ridden on the exam. But if you calibrate it properly caffeine is an important part of your GMAT diet.

If you enjoyed the Effects of coffee on GMAT Prep, watch: Why a 4.0 does not equal GMAT success. 

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Posted on
16
Apr 2020

Combinatorics GMAT Problem: Movie Night

Today we’ve got a fairly straightforward GMAT combinatorics problem. If you’ve been self-prepping in a rigorous, let me review the rules sort of way, you’ll pick up that there’s orders, combinations here and you might be inclined to really dive in. What’s my combinations formula? What’s my permutation formula? How do I know which is which? Then plug in numbers.

While that will get you there understand that most GMAT combinatorics problems are more about being familiar with combinatorics than any really heavy duty math. That is because the number of people who are taking the GMAT are generally more familiar with Algebra or Geometry.

Combinatorics & The GMAT

Combinatorics, by virtue of being less known, is considered more valuable. It is scored more highly than problems of similar complexity in Algebra or Geometry. So you’re really being rewarded just for knowing basic combinatorics and in fact most permutation/combination problems fall into this basic category. The good news here is that you can use your reasoning to solve this problem without being burdened by the formal combinatorics formulas.

Solving The Problem

Let’s take a look at this problem. John’s having a movie night. We need to ask ourselves a series of pivot questions. How many different movies can John show first?

Well there’s 12 movies, he could show any of the 12. Leaving 11 movies to be shown second, any of 11. 10, 9. So the answer is 12x11x10x9 or 11,880. But even this math is a lot to do. Notice that by walking it through as a story, as a narrative, we don’t need to cancel out the 7 6 5 4 3 2 1. We don’t need to worry about division or anything else. We just know that there’s 4 movies and each time, each step we take, there’s one less movie available. Here we have this product 12 times 11 times 10 times 9, but we don’t really want to be forced to process this and so we can look for features that allow us to skip doing that heavy math.

Transforming The Numbers

We’ve got this really neat triangular shape in the answer choices where each answer has a different number of digits in it. 12, 11, 10, 9, we can look at and say on average each one’s about 10. The 9 and the 12 sort of compensate, but overall we’re going to have something that’s close to 10 times 10 times 10 times 10.

That is our answer should be somewhere around 10,000 or possibly a little more because we have an 11 and a 12 offset only by a 9. So what we’re looking for is something in that just above 10,000 range this prevents us from doing the math and very rapidly lets us look at those four movies, those numbers 12 11 10 9 and zero in on that 11 880 number.

Problem Form

Try it again with a similar number. Notice that you can’t do this with a hundred different movies selecting 17 of them. The math, the numbers would be too cumbersome.

The GMAT is really restricted here and you should restrict yourself to ones that are reasonable to keep processed in your head without doing heavy duty math. Similarly, notice how this one clusters around ten, it doesn’t have to cluster around ten, but when you’re rewriting this problem think about that clustering and think about how your knowledge of common powers or how other identities can help you rapidly get to an answer because the GMAT will present you with numbers that have a neat clean way to jump from your understanding directly to the answer without all that messy math in between.

This is Mike for Apex GMAT with your problem of the day.

If you enjoyed this combinatorics GMAT problem, try more GMAT practice problems:  Remainder Number Theory 

 

 

 

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Posted on
26
Mar 2020

How COVID-19 Is Affecting The GMAT And Its Test Takers

Mike is here with a special update video about how the COVID-19 is impacting the GMAT testing world. I wanted to share some big news with you guys from the GMAC, the makers of the GMAT, about a substitute exam that they will be using and that you should be able to take from home starting in the middle of April.

General Inquiries

So, first off, a lot of people are finding themselves in uncertainty about their application process and about their GMAT preparation. To be sure, we have been getting a lot of calls about people wanting to make the best use of their time while they are furloughed from work, or while they are working from home and have a bit more flexibility and to be sure it’s an opportune time to bite off this task which for most people is really hard to fit into their existing professional and personal lives.

Additionally, we have a lot of inquiries about what’s going to happen with admissions. We can’t speak for any particular schools, however, we expect that the window of the virus crisis is such that it won’t meaningfully impact applications for Fall of 2021, that is that by the time your first round comes around in September or October, you are going to be able to get in, take the GMAT as normal and be able to apply and go to other events.

That of course is the hope and this is an emerging phenomenon, and emerging circumstance on the world stage without much precedence. So of course things are bound to change and we promise to keep you updated through the entirety of this crisis.

The New Exam

The new exam that the GMAC is rolling out will be taken from home and they are planning on rolling it out sometime in the middle of April. It will have three of the four GMAT sections, Integrated Reasoning, Quantitative and Verbal. So you will be able to get your score out of 800 with Quant and Verbal as well as your score for the Integrated Reasoning. The only section that will be missing is the writing section which I say is the least important of the entire GMAT from an admissions standpoint. The exam will be priced at a lower price point; they have not announced what that price point is but certainly at some discount to the normal $250 that’s charged.

Test Considerations

There are also some strategic considerations that come with this exam and some things we don’t yet know. For example, it is unclear as to whether you will get to choose the order of the sections when you take the exam or if it will be predetermined. Additionally, because the GMAC is likely using a different problem bank than they use for the actual GMAT, this makes some subtle time allocation and strategic guessing decisions change compared to the normal GMAT and I will be talking about that in another video.

If You Need Any Help Give Us A Call

I know that this is a stressful time for everyone who has business school and GMAT plans that have been disrupted. So if you need any help or need any advice, please feel free to visit our website: www.apexgmat.com.

You can contact us directly through there by chat, phone or email and from our entire family, we wish you health and safety in this difficult time and we’ll look forward to keeping you updated as soon as we have new information. Thanks so much and stay safe.

Watch other videos about COVID-19 and the GMAT: Here 

 

 

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