Problem:
The diagram shows an octagon consisting of 10 unit squares. The portion below PQβ is a unit square and a triangle with base 5. If PQβ bisects the area of the octagon, what is the ratio QYXQβ.
Answer Choices:
A. 52β
B. 21β
C. 53β
D. 32β
E. 43β
Solution:
The area below PQβ is
1+21ββ
5β
(1+QY)25ββ
(1+QY)1+QYQYβ=5=4=58β=53ββ
Then XQ=1βQY=1β53β=52β, so QYXQβ=3/52/5β=32β.
Answer: Dβ.
The problems on this page are the property of the MAA's American Mathematics Competitions