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The diameter of a sphere is decreased by...

The diameter of a sphere is decreased by 25%. By what per cent does its curved surface area decrease?

A

`63.75 %`

B

`53.75 %`

C

`44.75 %`

D

`43.75 %`

Text Solution

Verified by Experts

The correct Answer is:
D
`d_2=d_1-1/4d_1`
`d_2=3/4d_1`
=`(d_2-d_1)/d_1*100`
=`(4pi(r_2^2-r_1^2))/(4pir_1^2)*100`
=`(((3d_1)/4)-d_1^2)/d_1^2 *100`
=43.75.
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