Question

the ratio of diameter and height of right circular cylinder is 4:3 . if diameter of cylinder get reduced by 25% than its total surface area reduced to 318.5 sq meter . what is circumference of the base of the cylinder ?

Answer 1

The ratio of diameter and height of right circular cylinder is 4:3 .

Ratio of radius and height is 2:3

radius = 2x and height =3x

Total surface area of cylinder  = 2pi r(r + h)

T S A = 2pi.2x(2x + 3x)=20 pi x^2

if diameter of cylinder get reduced by 25%

then, TSA = 2 pi 2x(3/4)[2x(3/4) + 3x] =27 pi x^2 =318.5

x=2.7

radius r = 2x= 5.4

circumference of the base of the cylinder = 2 pi r= 2 x 3.14 x 5.4 =33.9m