Even the best GMAT test-takers will choose the wrong answer occasionally.

GMAT mistakes fall into two categories: careless errors and concept errors.

Let’s use this question (which comes from our Question of the Day blog), to illustrate the difference between the two types of errors.

In the 1930s, John W. Campbell wrote short stories about an Antarctic research camp that discovers and thaws the ancient body of a crash-landed alien and eventually combined them in a novella forming the basis of the blockbuster movie “The Thing.”

(A)  forming the basis of the blockbuster movie

(B)  that were forming the basis of the blockbuster movie

(C)  to form the basis of the blockbuster movie

(D)  which had formed the basis of the blockbuster movie

(E)  that formed the basis of the blockbuster movie

When we evaluate this question carefully, we see that E is the correct answer. However, someone who hadn’t studied their modifiers might choose A without realizing that forming illogically modifies research camps.

In other words, a concept error is the result of a fundamental misunderstanding of the material. 

The best way to minimize concept errors is to go back to the source. Review your notes and take a look at similar questions.  If you’re still struggling, reach out to other test-takers or consider contacting a tutor.

Careless Errors

On the other hand, an example of a careless error would be if the test-taker misread a part of the original sentence or one of the answer choices. Another example of a careless error would be a simple arithmetic mistake on a quant question. With careless errors, it’s a question of spending enough time and attention on the question to apply the knowledge you’ve already demonstrated on other questions. Careless errors can also be the result of a bad habit, such as forgetting to square x every time you’re faced with a certain formula.

All too often, test-takers will make the mistake of brushing off a careless error and tell themselves that they wouldn’t have missed it if they had noticed x or hadn’t forgotten about y. But ignoring careless errors dooms you to repeating the same mistake over and over again.

The best ways to minimize careless errors are as follows:

1. Reread.  Don’t be afraid to read the question a second time before you even start eliminating answers. And when you think you’ve solved it, take one last look at the original question to make sure that you’re answering what you’re supposed to be answering.
2. Look for patterns. Careless errors are not nearly as random as some test-takers seem to think. You might need to review a concept or slow down on certain questions.
3. Use more scratch paper. The more you try to do in your head, the more mistakes you will make. And the sloppier your writing, the easier it is to mix up 3 and 8.
4. Ask yourself why. Don’t just choose the answer that “fits” or “sounds right.” Take the time to ask why all of the other answers are wrong.

Of course, there’s nothing wrong with getting a question wrong. The problem comes when you don’t take the time to evaluate the question and ask yourself why you missed it.

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