Two Minutes of GMAT Quant: A Breakdown – Part 1

Two minutes is not a huge amount of time. Yet if you want to finish the entire GMAT Quant section in 75 minutes, two minutes is about all you have to solve each problem. Don’t interpret that to mean you just have to go quickly or skip important steps like checking your work. Instead, seek out a more efficient process for dealing with GMAT problems.

Better yet, read along as I detail an efficient process for dealing with your two minutes.

The First 5 Seconds: Glance

GMAT problems can be very helpful. They are full of hints that direct your process. The trick is knowing how to find those hints. For Problem Solving, start with a quick glance at the answer choices.You’re looking for two things: 1) Are the numbers arranged in any particular way that hints at what you’ll need to focus on and 2) Do the answer choices indicate any alternate strategies that might be helpful?

If you find your focus in the answer choices, you’re at an incredible advantage. Take a look at these three sets of answers, each of which has a huge hint, to see if you can already spot them.

Set 1:

1. 005
2. 05
3. 5
4. 5
5. 50

Set 2:

1. 1/2 > M > 1/3
2. 1/3 > M >1/4
3. 1/4>M > 1/5
4. 1/5 > M > 1/10
5. 1/10 > M > 1/20

Set 3:

1. 16%
2. 38%
3. 50%
4. 62%
5. 84%

What did you see? Let’s look set-by-set.

Set 1: For Set 1, you should have noticed that each answer is 5*some power of 10. It’s only the decimal that moves. The hint is that you already know the numerical answer. It’s 5. What you don’t know is where the decimal should be, so that needs to be your focus when you dive into the problem.

Set 2: Set 2 is strikingly different. The problem will clearly ask you to solve for M, but the answers hint at a shortcut. Because M is given in a range, you shouldn’t need an exact value. Instead, if you can approximate it, you’ll be able to cut your time down.

Set 3: You’ll find many GMAT problems that ask for a percent value, as Set 3 does. The hint is that the answers contain not only the right answer, but also the trap answers. Imagine the problem asks you to solve for percent of x in a group of x’s and y’s. Imagine also that the percent of x is actually 62%, answer (D). Using perfectly accurate math, you solve the problem and determine that x = 62% and y = 38%. In the heat of the moment, you jump at the number you correctly solved for and pick 38%, answer (B). Perfect math, zero credit. (We call this kind of right-answer/wrong-answer relationship “Twins.” It’s pretty common.)

So at this point you’re worried enough about falling for the trap, and you’re probably saying “The hint here is to be careful in my calculations? What kind of hint is that? I always have to careful, now I’m just more stressed about it.” Well said, you.

We will never tell you the hint is to be more careful. That’s not helpful. Here’s the real hint: Your next step should be find a way to avoid the trap. The question asks you to solve for x, but don’t jump to that. Start my eliminating the trap answers. Two of the answer choices above 50%, two are below it, and one is exactly 50%. When comparing x and y, you have three options: x is greater, y is greater, or they are the same. If you can reason through the explanation and see that x must be greater than y, you can eliminate A, B, and C, knocking out the trap answers.

The answer choices can also point toward alternate strategies. See if you can pick which ones in these examples:

Set 4:

1. x²–4
2. (x – 2)²
3. x² / 4
4. 4x²
5. 4 – x²

Set 5:

1. 1,200
2. 800
3. 600
4. 400
5. 200

Set 6:

1. 10,635
2. 5,387
3. 1,382
4. 524
5. 23

Each of these answers lets you know the problem can be solved indirectly. If you’re comfortable with our alternate strategies, hopefully you spotted at least two out of the three.

Set 4: Set 4 is perfect for smart numbers or testing cases, depending on the set up. Pick a value for x, plug in, and see which answer produces the desired answer.

Set 5: Set 5 sets you up for working backwards. The answers are easy to compute with, so start with the answers instead of the problem.

Set 6: Set 6 is less obvious. You shouldn’t try to work backwards with this one because those numbers would be ugly in computations. They’ll also probably be ugly to solve for. Here’s a crazy idea: Don’t worry about the actual answer. Each choice is drastically different from the others. Tackle this one by estimation. Should it be less than 10,000, but significantly higher than 1,000? B is your answer. Figuring that range out shouldn’t be too hard.

This has been a rather long post and we’ve only made it through the first five seconds of your two minute time allocation.Check back soon for the next edition of the two-minute breakdown.

More importantly, all of this analysis should take you only 5 seconds. Are you already comfortable with that? Probably not yet, but you can be. Open your OG to any problem solving page. Pick a problem. Do not solve. Cover up the actual problem and just examine the answer choices. Take your time and see what you can figure out. Then solve the problem using the hints and strategies you’ve already figured out. Keep practicing your analysis of answer choices, each time giving yourself a little less time. Once you can get a good hint or two from the answer choices in only 5-10 seconds, you’re ready to focus on the next step.

Of course, the most in-depth way to learn the ins-and-outs of GMAT Quant is to take a complete course with one of our master instructors. Try out any first session for free! No strings attached.

Emily Madan is a Manhattan Prep instructor based in Philadelphia. Having scored in the 99th percentile of the GMAT (770) and LSAT (177), Emily is committed to helping others achieve their full potential. In the classroom, she loves bringing concepts to life and her greatest thrill is that moment when a complex topic suddenly becomes clear. Check out Emily’s upcoming GMAT courses here. Your first class is always free!

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