Know the fundamentals
To do well on the GMAT quant, you can’t guess your way through, relying on techniques such as process of elimination or approximation. At a certain point you have to know the properties of a right triangle or the difference between dependent and independent events in probability.
Of course the range of concepts tested on the GMAT is relatively vast. Wouldn’t it be great if everything from mixture problems to equations with square roots was covered in one place? Well, every math concept that can come up on the GMAT is covered in Magoosh’s lesson videos.
Know the GMAT
Say you studied math in college and have a solid grasp of the fundamentals. Surprisingly, you may not get a perfect score on the GMAT quant. In fact you may miss a number of questions. Part of the reason is that the GMAT is designed in a way to trick the test taker. For instance, failing to notice the word ‘ratio’ vs. ‘number’ can lead you to miss an easy question.
An indispensible skill—and one many do not learn in school—is approximating. Coming up with an answer that is close to the actual answer can help you save a lot of time. Plugging in and backsolving are a few of the other techniques that will help you solve question quickly and efficiently.
Be a Specialist
Do not spread yourself too thin by trying to learn a slew of different concepts at once. Focus on a couple of areas and become relatively good at them. What do I mean by ‘relatively good’?
Well, say you haven’t seen geometry in awhile. Learn the basics and approach problems at the easy to medium level. You may even want to segment geometry in the sense that you are focusing on one particular area, say triangles. Learn the properties, and spend a day or two answering the easy to medium questions.
On the other hand, do not spend two hours pulling your hair out over a difficult problem in which a triangle is inscribed in a circle and the explanation at the back of the Official Guide is leaving you flummoxed.
Be a Generalist – The GMAT garden
Imagine you have a greenhouse, filled with a variety of plants: rhododendrons sit beside of marigolds, geraniums lounge next to chrysanthemums. What would happen if you only watered the geraniums? Well, the chrysanthemums and marigolds would wilt. But even the geraniums would not fare so well, glutted with too much water.
The different concepts on GMAT math are much like the different flowers in our imaginary greenhouse. You do not want to spend too much time on one concept, letting what you learned previously wilt, as it were. Nor, to continue the metaphor, do you want to overwater the same plants. Plants, just like the neural connections in our brains, need time to grow in between watering.
To turn this into practice, review concepts you’ve already gone over. A great way to do so is to work through the OG guides. Concepts are scattered about randomly in both the Problem Solving and the Data Sufficiency sections. Encountering concepts you’ve already studied will be akin to giving the plants in your greenhouse a tiny spritz of water.
Of course, there will be concepts you haven’t seen before – but that you’ll get to in time. Skip these or try them anyways, as it is good to determine your weaknesses and strengths (continuing the plant conceit – some plants need more water than do others).
Awaken your calculator brain
This one is big—but is surprisingly oft overlooked. By doing mental math exercises (multiplying, dividing, etc.) you can save a lot of time on the test.
Some of you might balk thinking that calculating in your brain is either a waste of time or, at best, a perilous route. However, like any skill mental math is something that can be developed. By becoming adept at it you will move much faster through the test than you would furiously scribbling on the pad GMAT provides. Anyhow, writing numbers down hardly ensures that you will avoid making calculation errors.