There are 2 different kinds of guessing that test takers should apply on the Quant section of the GMAT – both of them are crucial to success on the GMAT. But in my years of tutoring, I have found that most people just aren’t aware of how different guessing techniques apply on the test…and as a result their scores suffer.
Unstrategic Guessing
When most test takers say they are “guessing” on the GMAT, what they really mean is that they are giving up after spending a couple of minutes on the question and then just selecting an answer. And although everyone will find themselves in that situation on the GMAT at one point or another, that kind of unstrategic guessing is to be avoided. The problem is that you end up spending a lot of time with nothing to show for it. Spending 2 or 3 minutes on a question and then having to make a completely blind guess is a killer and yet people fall into the trap of doing that all the time on the GMAT. You shouldn’t be committing to spending 2+ minutes on a question unless you believe you have a very good chance of answering it correctly or at least narrowing down the answers to make a good strategic guess.
The Different Types of Guessing Explained
Really there are 2 types of strategic guessing that you should try to apply, especially with regard to Problem Solving questions (I will explain more about Data Sufficiency below). The first is when you read a question, realize that you don’t really know how to attack it, and give up and guess immediately. The guess itself might not seem strategic, but the decision to immediately let go of the question and guess is! The other situation is when you think you have some chance of making headway on the question and are willing to spend a minute or 2 in order to make a better educated guess or, if you are lucky, discover the path to the answer. Both of these kinds of guesses have a place on the GMAT, especially from a time management perspective, so let me explain when they each cab be useful.
Guessing to Gain Back Time
There will almost certainly be questions on your GMAT (perhaps many) that are clearly too hard and that you probably shouldn’t even attempt to solve. This is a difficult pill for many people to swallow but it is just a fact of the test. Many test takers foolishly waste time trying to solve every question. But they would be better off spending a little extra time on questions that they probably can answer and quickly dumping questions that they cannot. Many people spend 1.5 or 2 minutes minimum on every question so they never give themselves a chance to gain back time for the questions that they spend 3+ minutes on. But, if when a question comes on the screen you can quickly identify it as a low percentage question and if it seems like spending some time on it is not even likely to yield an educated guess, then you should immediately dump the question and move on.
Yes, you will probably get the question wrong, but that is the great thing about the quant section of the GMAT: you can get a lot of questions wrong and still have a great score. Why waste time on something that you will likely get wrong anyway? If you can spend 20-30 seconds and then dump a question, and if you can do that on 3 or 4 or 5 question on the test, you can gain back 5 or 6 or 7 minutes that you can then apply to other questions (ones that you can answer but that require more than 2 minutes).
An example of the above is a hard combinations/permutations question. These questions are usually very difficult and they also don’t lend themselves to strategic guessing. Plus, they are easily identifiable. Most people see those questions and say, “oh shit!” Yet most people still attempt to solve them even when it is pretty clear that they are in over their head. Do yourself a favor: if you recognize that the question is one that you don’t really know how to solve and if you don’t think that playing with it is likely to lead to an answer or to a very good educated guess, just guess and move on!
Guessing to Not Lose Time
This probably sounds the same as the type of guessing that was just described, but it is actually a little different. Whereas the above guessing is aimed at gaining back time, the other kind of guessing is not going to gain you back time, but it will prevent you from falling further behind on the test – sort of like damage control. Now, I am not talking about spending 2 minutes, realizing that you are not going anywhere, and then making a fairly random guess. In tutoring I have seen that many GMATers have a very good internal clock set at 2 minutes – basically what they do is “go for it” on every question and then at around 2 minutes if an answer isn’t in sight they just give up and guess (usually unstrategically). Again, that is not a very good way to succeed on the test.
If when you first look at the question you are not sure if you can solve it but if you see that you might be able to eliminate some answers and make a pretty good educated guess, then it would probably be worth spending a little time on it in order to make that guess. This takes some time, however, and that is why this guessing method is a little different from the previous one. In this case you will need to think through the question some, you may need to play with the answer choices a little, do a few calculations, etc. That will probably cost you close to 2 minutes. But if that allows you to come up with a pretty good educated guess then it is probably worth that time.
An example of this type of scenario would be a geometry question. Some geometry questions are very hard, but because figures are always drawn to scale unless otherwise noted on Problem Solving questions (not the case on Data Sufficiency), one can often make an educated guess just by looking at the figure, using some logic, and glancing at the answers to see what is reasonable. So in that kind of case it might be worth spending 1.5 or 2 minutes on the question to see if you can make some headway or make a good educated guess.
Data Sufficiency
Data Sufficiency is a little different, in my opinion, when it comes to guessing. If you understand Data Sufficiency well it is usually possible to make a pretty good educated guess on almost every question. Therefore, I would almost never do a 30 second dump on a DS question. I might not spend 2 minutes because in some cases it would be clear that the question is really hard and/or really time consuming, so I might be looking to move on and not waste a lot of time on the question, but I would not just make a blind guess in order to move on. I would just try to quickly eliminate what is obviously wrong and then make an educated guess based on the 2 or 3 possibilities that seem most likely after a quick assessment. In the end that may take only 1 minute or maybe a little bit more, so DS often presents itself as an opportunity to make back a little time if you are falling behind. And if you are really “Data Sufficiency savvy” and especially if you avoid the sucker answer, you have a very good chance of getting the question right anyway.
Conclusions
The key in all of this really is to assess your chances on any particular question (and I mean really assess and think about how you would solve it or whether you think you even can) before diving in and spending time on it. In my years of tutoring I have found that very few people really do this. They usually just “go for it” on every single question and then dump the question, making a pretty unstrategic guess, after about 2 minutes.
This is a recipe for failure, especially for people who tend to work slowly or who just can’t seem to get to right answers in about 2 minutes (and there are many, many people who fall in that category). The way the scoring algorithm works, you are likely to get about half of the Quant questions wrong anyway, so it really pays to take some time up front to consider what your best option is: should you go straight for it or perhaps completely dump the question and gain 1.5 minutes back, or maybe spend a little bit of time working with the question so that when you do guess you have a better than 20% chance of picking the right answer. Applying this overall strategy will put you in the driver’s seat and prevent you from feeling like you are constantly behind, frantically rushing, and never having enough time to really think clearly in a way that allows you to effectively answer the questions that you know you can answer.