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Question
The circumference of a circle is eigth time the circumference of the circle with a radius of 12 cm. Find its diameter.
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Solution
Let the radius of the bigger circle = R, and Let the radius of the smaller circle = r.
r = 12 cm
According to the problem,
2πR = 8 × 2πr
2πR = 8 × 2π × 12
R = `(8 xx 2pi xx 12)/(2pi)`
R = 8 × 12
R = 96
Diameter = 2 × 96
= 192 cm
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