GAUSS7 2015 Problem 15

Past Contests GAUSS7 GAUSS (GR. 7) - 2015
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1

In the rectangle shown, the area of the shaded region is

Image

Answer Choices
A. 60\:cm^2
B. 20\:cm^2
C. 30\:cm^2
D. 40\:cm^2
E. 50\:cm^2