CAYLEY 2005 Problem 9

Past Contests CAYLEY 2005
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1

ABCD is a rectangle, with M the midpoint of BC and N the midpoint of CD. If CM=4 and NC=5, what percent of the area of the rectangle is shaded?

Image

Answer Choices
A. 70
B. 78
C. 80
D. 87.5
E. 75