SOLUTION: A circle of radius 12 inches has its radius decreased by 8 inches. By what percentage has its area been decreased?

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Question 316480: A circle of radius 12 inches has its radius decreased by 8 inches. By what percentage has its area been decreased?
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
.
.
.
A1=pi%2A12%5E2=144%2Api
A2=pi%2A8%5E2=64%2Api
DELTA=%28A1-A2%29%2FA1=%28%28144-64%29%2Api%29%2F%28144%2Api%29=0.556
.
.
.
55.6% decrease in area.