12 things you can do to avoid careless math mistakes on the GRE and GMAT
1) Take Careless errors REALLY seriously.
The number 1 mistake people make is to not analyze their careless errors, take them into account, or figure out how to avoid them!
For example: “I got a 153 but made 5 careless errors, so my score should have been higher.” No, what this tells us is that we have to really work hard at avoiding careless mistakes! If you made 5 geometry errors in one exam, you would work to improve your geometry skills, right? Same for careless mistakes.
3) Diagnose and categorize your careless errors. Everybody is different. Know yourself. Every time you make a careless error, figure out what type of mistake it was.
Was it a copying error (they said the car was going 42 m/h and you wrote 24 m/h)?
Was it a computational error (3*8 = 32)?
Was it a reading comprehension error (they asked for Annie’s speed, and you answered with Annie’s time)?
Was it a positive negative error ( -4 * 5 = 20)?
Was it a distributive error ( x - 4(5 + 3) = x - 20 + 12)?
Figure out your most likely candidates for careless errors. Once you categorize the errors, this will help you be more careful every time you come upon this situation.
4) Organize your notes well
Have the same system of taking notes for each problem.
Make sure your handwriting is clear--sometimes people make mistakes by misreading their own handwriting.
7) Reread the question part before answering the question.
Sometimes they say “what is x + 1?” You’ve done all the hard work on getting to x, but if you don’t reread the question, you may forget that they were actually asking for x + 1.
8) Minimize mental math
Write out as much as possible Even if you’re great at mental math and can do it with 95% accuracy--that means that 1 out of 20 calculations will be an error! Assuming there are 5 or so calculations in one problem, that means you will miss 1 out every 4 questions using mental math based on mental math errors alone. This is totally not worth it.
9) Reduce Before you Multiply (RBM)
This cuts down on number of errors, since we’re dealing with smaller numbers
for example:
48/32
= (6*8)/(4*8)
= 6/4
= 3/2
10) Write out relevant formulas on top of questions. This also helps to give you time to think about the problem beforehand to make sure you are doing the problem the quickest way
11) Double check all of your computations.
