How to avoid silly mistakes and careless errors on the GMAT, by a 750 scorer (and GMAT tutor)

If you’re looking at this blog post, you’re probably feeling quite frustrated right now. You might have just taken a practice test or done a huge chunk of quant practice, and it did not go as intended.

Instead of a gleaming edifice representing the hard work and dedication you’ve put into this exam thus far, your work is riddled with careless errors, resembling more a busted out old factory than an immaculate monument.

Obviously you have to fix these careless errors. But how do you do so, when they seem so random? They just seem to fall out of your pen.

Here’s how, in order of what you should try from first to last:

1) Make sure the mistakes are actually careless. As a GMAT tutor, I hear my students say all the time, “Oh, that was just a dumb mistake.” And then, when I ask them to do the question again on a blank sheet of paper, they make the same mistake again, or are unable to do the problem correctly.

In other words, the mistake wasn’t actually careless! It was a systemic mistake, caused by either a lack of content understanding or an error in process. Either way, careful use of an error log (like my error log app, 21st Night), is key for avoiding these sorts of mistakes in the future.

2) Take meaningful notes while you’re working. The most common reason for careless errors is terrible note-taking. Frequently, I will glance at my student’s work and it will look like a secret code: “x=5 24, 47=12 miles per hour”.

If you take notes like this, you place a tremendous mental burden on yourself. Not only do you have to solve the problem, but you have to keep track of everything else as well. The more stuff there is to keep track of, the easier it is to mess up one of them.

To fix this, look back at your notes after the problem is completed. They should make sense. If they don’t, redo the problem through the error log, and take proper notes this time.

3) Do timed sets of the same sort of problem. If a mistake is really careless, meaning that it’s not a problem with your content, your process, or your notetaking, then you should do timed sets.

Do 20 or 30 questions in a row, and give yourself 2 minutes per question. Not only will this give you lots of practice, but it’ll build up the stamina you need in order to answer questions even when you’re exhausted.

After all, part of why the GMAT is so tough is that it’s a loooong exam, and mentally draining. Careless errors often come about when you’re too tired to do problems properly. This way, you’ll learn to build up that stamina and avoid careless mistakes.