SOLUTION: The inner circumference of a circular track is 242m. The track is uniformly 7 m wide. Find the area of the track.

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Question 1071210: The inner circumference of a circular track is 242m. The track is uniformly 7 m wide. Find the area of the track.
Answer by josgarithmetic(39618) About Me  (Show Source):
You can put this solution on YOUR website!
Two concentric circles.
Inner circle:
2pi%2Ar=242
r=121%2Fpi

Outer circle's radius is 121%2Fpi%2B7.


Area of the track is the difference between outer and inner circles' areas.
pi%28121%2Fpi%2B7%29%5E2-pi%28121%2Fpi%29%5E2

pi%28%28121%2Fpi%2B7%29%5E2-%28121%2Fpi%29%5E2%29

pi%28%28121%2Fpi%2B7%2B121%2Fpi%29%28121%2Fpi%2B7-121%2Fpi%29%29

pi%28%28242%2Fpi%2B7%29%287%29%29

pi%281694%2Fpi%2B49%29

highlight%281694%2B49pi%29