SOLUTION: the circumference of a circle is 56.52 inches, to the nearest tenth of an inch find the area of the circle. use pi=3.14

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Question 120442: the circumference of a circle is 56.52 inches, to the nearest tenth of an inch find the area of the circle. use pi=3.14
Found 2 solutions by bucky, josmiceli:
Answer by bucky(2189) About Me  (Show Source):
You can put this solution on YOUR website!
The equation for the circumference of a circle is:
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C+=+2%2Api%2AR
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Where C represents the circumference and R represents the radius.
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The problem tells you that C = 56.52 inches and pi=3.14. Substituting these two values
into the equation for the circumference results in:
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56.52+=+2%2A%283.14%29%2AR
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Multiply out the constants on the right side to get:
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56.52+=+6.28R
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Solve for R by dividing both sides of the equation by 6.28 to get:
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R+=+56.52%2F6.28=9
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The radius of the circle is 9 inches.
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The area of a circle is given by the formula:
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A=pi%2AR%2A2
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in which A represents the area, again pi+=+3.14, and for this problem R = 9 inches.
Substituting the values into the equation results in:
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A+=+%283.14%29%2A%289%5E2%29+=+3.14%2A81+=+254.34
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The area of the circle is, therefore, 254.34 square inches. The problem tells you to round
this to the nearest tenth of an inch. Rounding gives you the final answer of 254.3 square inches.
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So the answer is that the Area of this circle is 254.3 square inches.
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Hope this answer helps you to see your way through this problem.
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Answer by josmiceli(19441) About Me  (Show Source):