# What is the ratio of the red area to the blue area?

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Three semicircles (with equal radii) are drawn inside the large semicircle so that their diameters all sit on the diameter of the large semicircle. What is the ratio of the red area to the blue area?

posted Jun 8, 2016

Let the diameter of larger circle is r, so now radius of one small circle is r/6
total are of smaller circle: PIE*r^2/12
total are of larger circle: PIE*r^2/4
ratio=1/3

IM DISAPPOINTED YOURE TRYING TO CHEAT...

answer Mar 22, 2017 by anonymous

Area of small semicircle A1=Pi.r^2/2
Area of big semicircle B1=9.Pi.r^2/2
Red area A=3.Pi.r^2/2
Blue area B=B1-A=9.Pi.r^2/2 - 3.Pi.r^2/2 = 3.Pi.r^2
Ratio A/B= 1/2

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