Problem:
If the product 23⋅34⋅45⋅56⋅…⋅ba=9, what is the sum of a and b?
Answer Choices:
A. 11
B. 13
C. 17
D. 35
E. 37
Solution:
Since 23⋅41⋅52⋅⋯⋅ba=9, we see that 2a=9. Thus, a=18, b=17, and a+b=35.
Answer: D.
The problems on this page are the property of the MAA's American Mathematics Competitions