Question

Before taking a typing course, Frank could type 27 words per minute by the end of the course he was able to type 77 words per minute. Find the percent increase.

A 185.2%
B 74%
C 35.1%
D 64.9%

Answer 1

% Change is ALWAYS (end point - starting point) / (starting point)
end point is 77
starting point is 27
% change = (77-27) / 27
= 50 / 27
= 1.85, or 1.85 X 100 = 185%
Since he increased his typing speed, it's correct to call the % change a % increase

A brief word about our calculation:
For 50 / 27 we got 1.85, and that's the correct answer. Note that 1.85 is really 1.85 / 1
Since they want % change, we need to remember that the % sign stands for "per hundred",
and we only have 1.85 / 1 , or per one.
Simply multiply top and bottom of 1.85 / 1 by 100 to get 185/100, or 185%