SOLUTION: the radius of a circle is decreased by 8%. The % difference of the area of the circle is? Can you please show me the steps?

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Question 338905: the radius of a circle is decreased by 8%. The % difference of the area of the circle is? Can you please show me the steps?
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
The area of a circle is,
A=pi%2AR%5E2
If the radius is increased 8%, then
R2=R%281%2B8%2F100%29=1.08R
The new area is,
A2=pi%2AR2%5E2=pi%281.08R%29%5E2=1.1664%2Api%2AR%5E2
The ratio of new area to old area is
A2%2FA=1.1664 or a 16.64% increase in area.