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## Write Your Own GMAT Practice Questions

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It's often said that the only way to really learn something is to teach it; when it comes to GMAT quant problems, you could say the only way to really learn something is to create it.

Often, I hear students complain that they are running out of practice material, or that they'd like to have five more questions on a specific topic, such as combined rate. Those are reasonable concerns: certainly, if you're struggling with a content area, you should find more opportunities to improve your skills. Here's how you can do it.

When I write practice GMAT questions, I hew as closely as I can to the real thing. Sure, I change the names of the variables, I change the numbers around a bit, and if it's a word problem, I change the setting, so that you don't immediately recognize where the problem came from. But despite all of those changes, my practice question tests exactly the same things that the original did–by design.

One of the topics I've repeatedly come back to since starting this site is how much you benefit from increased familiarity with numbers–specifically, the numbers that come up frequently on the test. If you walk through the same process I just described, you will find yourself thinking about numbers in a whole new way. Create your questions with the knowledge that the numbers should "work out," and you'll be working with 72, 64, and 30, the same way the GMAT does.

To get started writing your own variations on GMAT questions, take a problem (preferably from The Official Guide) that you're not 100% comfortable with. Then start asking yourself "what if?"

• What if x was negative?
• What if there were four coins instead of three?
• What if the figure were a 30:60:90 triangle instead of an isoceles right triangle?
• What if you added two or subtracted two from one of the numbers?

How you change the question will differ in every single example. It's a test of imagination nearly as much as a test of knowledge. But if you generate, say, 10 new GMAT questions, you're much closer to being inside the head of the testmaker. By extension, you're that much more prepared for what the GMAT will throw at you when you take the real thing.

About the author: Jeff Sackmann has written many GMAT preparation books, including the popular Total GMAT Math, Total GMAT Verbal, and GMAT 111. He has also created explanations for problems in The Official Guide, as well as 1,800 practice GMAT math questions.

 Total GMAT Verbal The comprehensive guide to the GMAT Verbal section. Recognize, dissect, and master every question type you'll face on the test. Everything you need, all in one place, including 100+ realistic practice questions. Click to read more.