The radius of a circle is increased by 85%. How much will the area increase in percent? Round your answer to the nearest tenth if a percent.

Question

I'm stuck on this question. Thanks
-Zach

Answer 1

original area = pi(1^2) = pi
new area = pi(1.85^2) = 3.4225pi

increase = 3.4225pi - pi = 2.4225pi

percentage increase = 2.4225pi/pi = 2.4225
= 242.3 %