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Question
If the radii of two circles are in the ratio of 4 : 3, then their areas are in the ratio of ______.
Options
4 : 3
8 : 3
16 : 9
9 : 16
Solution
If the radii of two circles are in the ratio of 4 : 3, then their areas are in the ratio of 16 : 9.
Explanation:
Let radii of circles are r1 and r2
Given: `r_1/r_2 = 4/3`
`(pir_1^2)/(pir_2^2) = r_1^2/r_2^2`
= `(r_1/r_2)^2`
= `(4/3)^2`
= `16/9`
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