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प्रश्न
The circumferences of two circles are in the ratio 4 : 5. What is the ratio of their radii?
विकल्प
16 : 25
25 : 16
`2 : sqrt(5)`
4 : 5
उत्तर
4 : 5
Explanation:
Given,
Ratio of circumferences of two circles = `4/5 = (2πr_1)/(2πr_2)`
`\implies r_1/r_2 = 4/5`
`\implies` r1 : r2 = 4 : 5
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