1953 AHSME Problems/Problem 11
A running track is the ring formed by two concentric circles. It is feet wide. The circumference of the two circles differ by about:
Solution
Since the track is 10 feet wide, the diameter of the outer circle will be 20 feet more than the inner circle. Since the circumference of a circle is directly proportional to its diameter, the difference in the circles' diameters is simply feet. Using , the answer is .
See Also
1953 AHSC (Problems • Answer Key • Resources) | ||
Preceded by Problem 10 |
Followed by Problem 12 | |
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