Problem:
Which of the following operations has the same effect on a number as multiplying by  and then dividing by 
Answer Choices:
A. dividing by  
B. dividing by  
C. multiplying by  
D. dividing by  
E. multiplying by  
Solution:
Since , multiplying by has the same effect.
Answer: .
The problems on this page are the property of the MAA's American Mathematics Competitions