Question

The height of a right circular cylinder is 10/5 m. Three times the sum of the areas of its two circular faces is twice the area of the curved surface. Find the volume of the cylinder.

Answer 1

We have,

Height of cylinder = 10.5 m

3(A+A) = 2 curved surface area (where, A= circular area of box)

3×2A = 2(2πrh)

6A = 4πrh

6πr² = 4πrh

r²/r = 4πh/6π

r = 2/3 h

= 2×10.5 / 3

= 7m

∴ Volume of cylinder = πr²h

= 22/7 × 7 × 7 × 10.5

= 1617 m³