Problem:
All of the triangles in the diagram below are similar to isosceles triangle , in which . Each of the smallest triangles has area , and has area . What is the area of trapezoid
Answer Choices:
A.
B.
C.
D.
E.
Solution:
The length of the base of is 4 times the length of the base of a small triangle, so the area of is . Therefore the area of is the area of minus the area of , which is .
The problems on this page are the property of the MAA's American Mathematics Competitions