AMC 10A 2002 Problem 6

Cindy was asked by her teacher to subtract 3 from a certain number and then divide the result by 9 . Instead, she subtracted 9 and then divided the result by 3 , giving an answer of 43 . What would her answer have been had she worked the problem correctly?

Answer Choices
A. 15
B. 34
C. 43
D. 51
E. 138