The ratio of the area of circle \(A\) to the area of circle \(B\) is 4:1. What is the ratio of the circumference of circle \(A\) to the circumference of circle \(B?\)
A. 1:3
B. 1:1
C. 2:1
D. 4:1
E. 8:1
[spoiler]OA=C[/spoiler]
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The ratio of the area of circle \(A\) to the area of circle \(B\) is 4:1. What is the ratio of the circumference of
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Let the radius of circle A be R and the radius of circle B be r. We can create the equation:
(πR^2) / (πr^2) = 4/1
R^2 / r^2 = 4
R^2 = 4r^2
√(R^2) =√(4r^2)
R = 2r
Now let’s compare the circumferences of the two circles by substituting 2r for R:
(2πR) / (2πr) = R/r = 2r/r = 2/1
Answer: C
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