1. A student raises her grade average from a 75 to a 90. What was the percent of increase in the student’s grade average? Round your answer to the nearest tenth of a percent, if necessary.

A: 20%
B: 16.7%
C: 8.3%
D: 15%

6 answers

i think it is 20 am i right
No. Use method indicated in your following post.
you are correct

(90 - 75) / 75 = 20%
I am quoting this from a website: "To calculate percentage decrease: First: work out the difference (decrease) between the two numbers you are comparing. Then: divide the decrease by the original number and multiply the answer by 100. If your answer is a negative number then this is a percentage increase." I believe this will help you out.
R_Scott, you are incorrect. It should be (99-75)/90.
no @PsyDAG, @R_Scott is right