Praxis Core For Dummies with Online Practice Tests, 2nd Edition

Chapter 18

Ten Common Math Errors to Avoid

IN THIS CHAPTER

Overlooking signs

Confusing similar formulas and terms

Freaking out over fractions

Knowing how to perform certain types of math operations is a big part of solving problems correctly, but it isn’t everything. Caution is also important. Avoiding common math errors involves both. Think back to times when you saw what you missed on math tests and thought, “Oh yeah, I had this mixed up with that!” This chapter helps you avoid that exact situation. Errors are always a threat. Don’t let them get you.

Misusing Negative Signs

In our observations, math mistakes occur most frequently when negatives are involved. Negatives are to math problems what land mines are to war zones, except they’re only dangerous to math scores. That’s the good news. When you see a negative sign, you should turn your level of caution up a notch or two. Such a small symbol has so much power to transform a quantity. Imagine being told that you have $1 million in a bank account and then being told, “Oh, I’m sorry. I didn’t see the negative sign. You have –$1 million. You are that much in debt.” It’s a completely different picture. One misuse of a negative ...