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Printsmc
geometry senior
Problem
(A)
(B)
(C)
(D)
Solution
The area of the entire outer shape is the area of sector , plus the area of sector , minus the area of triangle (since it is part of both sectors), plus the area of sector . We know , so the sector angles for and are degrees, and the radius of both of them is . The radius of is , and can be found using Pythagoras in triangle , giving and , so after doing all the calculations, the area of the entire outer shape is . To get the area of the smile, we need to subtract the area of semicircle , which is , so the answer is = .
Final answer
B