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Question
The circumferences of two circles are in the ratio 5: 7, find the ratio between their radius.
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Solution
The ratio of the circumference of the circle = 5: 7
Let circumference of the first ratio = 5x
∴ 2πr = 5x
⇒ r =`(5"x")/(2π)`
and the circumference of the second ratio = 7x
∴ 2πr = 7x
⇒ r = `(7"x")/(2π)`
The ratio between their radius =`(5"x")/(2π):(7"x")/(2π)`
= 5: 7
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