NandishSS wrote:

A certain college's enrollment at the beginning of 1992 was 20 percent greater than it was at the beginning of 1991, and its enrollment at the beginning of 1993 was 15 percent greater than it was at the beginning of 1992. The college's enrollment at the beginning of 1993 was what percent greater than its enrollment at the beginning of 1991 ?

A) 17.5%

B) 24%

C) 30%

D) 35%

E) 38%

Shortcut FormulaWhen there are only two successive percent changes, A and B, and the numbers are reasonable, there is a simple formula* to calculate the total percent change, in this case, percent increase:

A + B + \(\frac{A*B}{100}\) = total percent change

A here is 20

B here is 15

20 + 15 + \(\frac{20*15}{100}\) =

20 + 15 + \(\frac{300}{100}\) =

20 + 15 + 3 = 38 percent increase

ANSWER E

*"Successive Percentage Changes," in Percentages, Interest, and More, from GMAT Club, here:

https://gmatclub.com/forum/percentages-interest-and-more-208098.html#p1596558
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