A few speed suggestions for word problems:
1) Make sure your fundamentals are solid.
If you are going to turn a paragraph into equations and then solve those equations within 2 minutes, you can't afford to stumble on the algebra. You want to turn even a complicated sentence, such as "The increase in A’s rate is 40% less than the difference between B’s initial rate and twice A’s,” into a nice, workable equation:
An = Ai + .6(Bi -2Ai)
2) Recognize different problem types.
You want to determine what kind of problem you’re dealing with and get the appropriate setup going within the first 30 seconds. For instance, for a rate problem you need a Rate/Time/Work chart, while for an overlapping sets problem you need a Double-Set Matrix. If it takes you a long time to recognize the problem type and respond, your solution will go overtime.
3) Learn the variations.
For each problem type, what are the common variations? For instance, when do you add rates and when do you subtract? What kind of tricks or traps can you expect? Maybe you’re given data in hours and expected to convert to minutes, or maybe you’re given several percents, but they’re percents of different quantities. Put together a set of notes for each problem type, so you can track these sources of complication and be ready for them.
4) Repeat!
Don’t be too quick to do a million problems of each type. Instead, repeat a few good examples until they’re really smooth. You might redo one problem several times in a row until you feel you can execute each step easily. The idea is that even the toughest quant problem typically reduces to just a few steps. Figure out what those steps are and what made them difficult so that you know what to improve for next time. Once you’ve done a few problems this way, you can feel more confident when you see a new problem, because you'll be able to draw on your experience. “Oh, it’s one of
these. It reminds me of the problem where I did
this.”
5) Remember to let go.
The GMAT is not about perfection. Expect to get 10+ quant problems wrong, even if you’re shooting for a great score. Part of knowing your word problems well is knowing when to let go. The sooner you know that a problem is too hard to do in 2 minutes, the better. That way, you can save time for the problems that deserve your attention.
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