Question

the diameter of a sphere is decreased by 25%,by what percentage its volume decreases?

here we have to find decreased volume not CSA and I know Answer is 57.81 but I don't know how it came..so plz give me step wise correct and easy to understand Solution..


plz..
I will surely mark u as Brainliest if I will be satisfied.​

Answer 1

Answer:

Original Diameter =d

Original CSA=4π(

2

d

)

2

=πd

2

New Diameter =d−

100

25

d=

4

3d

New CSA=4π(

8

3d

)

2

=

16

9

πd

2

.

% decrease =

πd

2

(πd

2

−

16

9

πd

2

)

×100

=

πd

2

πd

2

(1−

16

9

)×100

=

16

16−9

×100

=43.75%.

solution