If the radius of a cylinder is reduced by 50 %, then volume of the cylinder gets reduced by
75%
Let the radius of the old cylinder be R and that of the new cylinder be r.
Then, r=R2
Volume of old cylinder = πR2h
Volume of new cylinder= πr2h
= π×(R2)2×h=π×R2×h4
Hence, reduction in volume = πR2h−π×R2×h4
=34πR2h
∴ percentage reduction
=34πR2hπR2h×100
=75%