Problem:
Zoey read books, one at a time. The first book took her day to read, the second book took her days to read, the third book took her days to read, and so on, with each book taking her more day to read than the previous book. Zoey finished the first book on a Monday and the second on a Wednesday. On what day of the week did she finish her th book?
Answer Choices:
A. Sunday
B. Monday
C. Wednesday
D. Friday
E. Saturday
Solution:
It took Zoey days to read the books. Because , it follows that Zoey finished the th book on the same day of the week as the first, a .
The problems on this page are the property of the MAA's American Mathematics Competitions