SOLUTION: if the radius of a circle is increased by 30%,then the area of the circle is increased by___________ ______

Algebra ->  Percentage-and-ratio-word-problems -> SOLUTION: if the radius of a circle is increased by 30%,then the area of the circle is increased by___________ ______      Log On


   

Question 715277: if the radius of a circle is increased by 30%,then the area of the circle is increased by__________________
Answer by Simnepi(216) About Me  (Show Source):
You can put this solution on YOUR website!
30%=3%2F10=0.3
if we call the radius x then the new radius is 1.3x
since area+=+pi+%2A+%28radius%29%5E2
squaring the radius gives 1.69%2A%28x%29%5E2
so the area has increased by
0.69 or 69%