When do you leave the house without directions? Or perhaps the more modern reference, is when do you start on your way without plugging in your destination into a GPS device? I expect the answer for most of you is “when I know where I am going.”
Conversely, when you have no idea when you are going, your solution is most likely not to get in your car (or on your bike or public transit) and just start randomly driving around hoping you run into your desired destination. Ideally, you probably look up where you are going and plan out a route. Alternatively, you might know a nearby destination and start heading there (e.g. I know the bike store is near that place I get coffee). Finally, on occasion you may just head to an area where you expect to find a type of business (e.g. Gas stations are usually close to freeway entrances).
Now, all this talk about directions has been fun, but let’s bring the analogy around to GMAT quant problems. Sometimes when you see a GMAT problem, you may understand what the question is asking and see the path to the solution. In these cases, dive right in. Start driving and you are likely to reach your destination because you know – or at least have a good sense – of where you are going.
At other times, you probably look at a GMAT problem and are not sure of what it is asking you or how you might possibly get to an answer. I have often seen students faced with such problems, probably propelled by the time constraints of the GMAT, start frantically writing with little sense of purpose. Their papers fill with writing, but often a solution is not reached. This approach is akin to just getting in your car and randomly driving around. While you are covering miles, you are more than likely not getting any closer to your destination. Just as with driving, taking the time to “get directions” on a GMAT problem actually saves you time in the end.
Unfortunately, there is no Google Maps of GMAT problems available to you on the test, making the directions you seek a little harder to come by. But there are several techniques you can use to help you get a better sense of where you are going so your work is more directed and less random.
1) Take the time to plan. Sometimes you may have the ability to generate your own plan, if you are just willing to take the time to think rather than jumping into immediate action. One exercise that can aid in these skills is doing a set or practice problems where you do not allow yourself to start writing for 45 seconds, forcing you to spend time understanding and planning. This approach still leaves you 1 minute 15 seconds for execution – plenty of time if you have a good plan in place.
2) Think of a similar problem. Although the joys of doing problems out of the Official Guide cannot be overstated, you are not doing all those practice problems just for fun. If you can remember a similar problem and how that problem was solved, this previous approach can serve as a jumping off point. Once you have identified a similar problem, be careful to still think about the nuances of the problem at hand as you may need to adjust the approach slightly. In order to be able to recall similar problems, it is very important to do a complete job reviewing the practice problems you do (more on ways to review you work here).
3) Categorize the problem. Even if you cannot identify a specific problem that relates to the problem at hand, you may be able to categorize the problem. Through this categorization, you should be able to identify the general approaches or equations that are used in solving this type of problem. For example if I see anything that says “per hour” or other time period I am thinking of a rate problem, which brings to mind the rate * time = distance/work equation. Then I must go on to think about the specific application of this technique to the problem.
4) Begin with an equal sign. Many GMAT problems are solved through equations, and all equations have one thing in common – the equal sign. In word problems, identifying what you are equating is often a great first step. For example, the problem might ask how many floors the building would have such that the time to walk the stairs is the same as the time to take the elevator. Conceptually this equation is time in elevator = time on stairs. Once I have identified this on a conceptual level, I can then work to turn the equation into math and identify what variables I might need (in this case probably n = number of floors).
5) Start with what you do know. Rarely will there be a problem on the GMAT where you understand nothing of what is being said (in those cases it is probably better to make a guess and move on). More often, you may find some aspects confusing, but some pieces approachable. In these cases, focus on what you do know and try to use that as your entry point into the problem. For example, suppose I got a problem about two functions.
f(x) = some long and confusing definition
g(x) = an even longer and more confusing definition
Then the problem asked, what is the value of in terms of x?
One option would be to freak out because the functions are confusing, but this approach is probably not optimal. The other way to go would be to recognize what I do understand. In the end, this problem is asking me to subtract fractions. I know that to subtract fractions I need a common denominator. Perhaps I could even look at the denominators in the answer choices to get clued in about what that denominator might be, and with this recognition I have at least gained entry into the problem. Perhaps these denominators may help to give me some understanding of what is going on with the two functions as I go back to their definitions and try to complete the problem.
To close with a nice cliché, like many endeavors, success on the GMAT is about working smarter and not necessarily harder. Proactively planning before you start working will take you a long way towards this goal.