Given the figure above, find the ratio of the area of the shaded region to the area of the unshaded region. Give your answer as a decimal number to two decimal places.
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Area of x = Area of rectangle - Area of half circle x = ( r × 2 r ) − ( 2 π r 2 ) = r 2 ( 2 − 2 π ) Area of y = Area of equilateral triangle − 3 × ( 6 1 Area of circle ) //sector with angle 60° y = 4 3 ( 2 r ) 2 − 2 π r 2 = r 2 ( 3 − 2 π ) Area of shaded = 8 x + 1 0 y = r 2 ( 1 6 + 1 0 3 − 9 π ) Area of unshaded = 1 0 × A r e a o f c i r c l e = r 2 ( 1 0 π ) the ratio = r 2 ( 1 0 π ) r 2 ( 1 6 + 1 0 3 − 9 π ) = 1 0 π 1 6 + 1 0 3 − 9 π ≈ 0 . 1 6