GMAT Math

Careless Mistakes on GMAT Math
a blog article by Mike McGarry

Those of us who work in GMAT test prep often hear students say things such as, "I really understand the math on the GMAT, but I just make a bunch of silly mistakes" or, "Careless mistakes are my biggest problem on the GMAT Quant: how can I make fewer of them?" Let's think about this. What exactly is a "careless mistake" or a "silly mistake"? I am going to discuss three different possibilities, all of which can play a part in the "careless mistake" issue.

Case One: Truly Silly Errors
Suppose, in the course of a calculation, you needed to calculate 2 + 4, and you said that this was 8. This is a very basic arithmetic calculation error, a truly silly mistake. We all make mistakes such as this sometimes. Every once in a while, one of my blog articles is published with such a mistake: fortunately, astute readers usually alert me in the comments. Everybody makes these mistakes, but they should be reasonably rare. If this happens more than once or twice on a 37 question section, then see Case Three. For most people, I don't think this is the kind of "careless mistake" that causes the most difficulty.

Case Two: Levels of Understanding
The opposite of careless is careful. - Suppose a student does a math question and gets the question wrong. Then, suppose the student reads the solution, and thinks, "Oh! To get the question right, I needed to use Concept X! I know Concept X!" Getting the problem wrong was a small mistake, but at this point, some students make a HUGE mistake by thinking: "OK, that was a just a careless mistake! I really understand this!" WRONG!! WRONG!! WRONG!!


See more at: https://magoosh.com/gmat/2013/careless-m ... gmat-math/