Question

Emily earned a grade of 80% on a math test that had 20 problems. How many problems on this test did she answer correctly? If John got 7 problems incorrect on the same test, what was his grade?

Answer 1

0.8*20 = 16 problems answered correctly
If John got 7 problems wrong, then he got 14 problems right.
14/20 = 0.7
Now, convert 0.7 into a percentage.

Answer 2

Someone getting all 20 problems correct would earn a grade of 100%. Thus, each correct question counts 5%.

If Emily earned 80%, then the number of problems she got correct was (80% / 100%).

Simplify this result. It represents the fraction of 20 questions that Emily got correct. Multiply your result by 20 to find the actual number of questions that E. got correct.