1953 AHSME Problems/Problem 11: Difference between revisions
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== Solution == | == 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 <math>20\pi</math>. Using <math>\pi \approx 3</math>, the answer is <math>\fbox{C}</math>. | 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 <math>20\pi </math> feet. Using <math>\pi \approx 3</math>, the answer is <math>\fbox{C}</math>. | ||
==See Also== | ==See Also== | ||
Latest revision as of 11:23, 22 April 2020
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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