Difference between revisions of "1952 AHSME Problems/Problem 33"
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A circle and a square have the same perimeter. Then: | A circle and a square have the same perimeter. Then: | ||
− | <math>\text{(A) their areas are equal}\qquad | + | <math>\text{(A) their areas are equal}\qquad\\ |
− | + | \text{(B) the area of the circle is the greater} \qquad\\ | |
− | + | \text{(C) the area of the square is the greater} \qquad\\ | |
− | + | \text{(D) the area of the circle is } \pi \text{ times the area of the square}\qquad\\ | |
− | + | \text{(E) none of these}</math> | |
== Solution == | == Solution == | ||
− | <math>\fbox{}</math> | + | |
+ | Assume that the side length of the square is 4 units. Then the perimeter for both shapes is is 4 * 4 = 16 units. Since the perimeter of a circle is 2πr, then 2πr =16 and r = 8/π, which is about 2.5. The area of a circle is πr^2 so (2.5^2)*π = 6.25π or about 19.6. This is more than the area of the square, which is 4^2 =16, so the answer is <math>\fbox{B}</math>. | ||
== See also == | == See also == |
Latest revision as of 12:15, 14 September 2020
Problem
A circle and a square have the same perimeter. Then:
Solution
Assume that the side length of the square is 4 units. Then the perimeter for both shapes is is 4 * 4 = 16 units. Since the perimeter of a circle is 2πr, then 2πr =16 and r = 8/π, which is about 2.5. The area of a circle is πr^2 so (2.5^2)*π = 6.25π or about 19.6. This is more than the area of the square, which is 4^2 =16, so the answer is .
See also
1952 AHSC (Problems • Answer Key • Resources) | ||
Preceded by Problem 32 |
Followed by Problem 34 | |
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All AHSME Problems and Solutions |
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