Difference between revisions of "2010 AMC 10A Problems/Problem 5"

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== Problem 5 ==
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The area of a circle whose circumference is <math>24\pi</math> is <math>k\pi</math>. What is the value of <math>k</math>?
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<math>
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\mathrm{(A)}\ 6
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\qquad
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\mathrm{(B)}\ 12
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\qquad
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\mathrm{(C)}\ 24
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\qquad
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\mathrm{(D)}\ 36
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\qquad
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\mathrm{(E)}\ 144
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</math>
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==Solution==
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If the circumference of a circle is <math>24\pi</math>, the radius would be <math>12</math>. Since the area of a circle is <math>\pi r^2</math>, the area is <math>144\pi</math>. The answer is <math>\boxed{E}</math>.
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==Video Solution==
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https://youtu.be/C1VCk_9A2KE?t=290
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~IceMatrix
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== See Also ==
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{{AMC10 box|year=2010|ab=A|num-b=4|num-a=6}}
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{{MAA Notice}}

Revision as of 06:19, 26 May 2020

Problem 5

The area of a circle whose circumference is $24\pi$ is $k\pi$. What is the value of $k$?

$\mathrm{(A)}\ 6 \qquad \mathrm{(B)}\ 12 \qquad \mathrm{(C)}\ 24 \qquad \mathrm{(D)}\ 36 \qquad \mathrm{(E)}\ 144$

Solution

If the circumference of a circle is $24\pi$, the radius would be $12$. Since the area of a circle is $\pi r^2$, the area is $144\pi$. The answer is $\boxed{E}$.

Video Solution

https://youtu.be/C1VCk_9A2KE?t=290

~IceMatrix

See Also

2010 AMC 10A (ProblemsAnswer KeyResources)
Preceded by
Problem 4
Followed by
Problem 6
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
All AMC 10 Problems and Solutions

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