SOLUTION: If the radius of a circle is increased by 30% then the area of the semi circle is increased by

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Question 469098: If the radius of a circle is increased by 30% then the area of the semi circle is increased by
Answer by ccs2011(207) About Me  (Show Source):
You can put this solution on YOUR website!
Let r,a be initial radius and area
Let R,A be increased radius and area
R = r + 0.3r (0.3*r = 30% of r)
R = 1.3r
a = %28pi%2Ar%5E2%29%2F2
A =
1.3^2 = 1.69
A = a + 0.69a
Therefore area increased by 69%