Question

Radii of circular ends of a solid frustum off a cone re 33cm and 27cm and its slant height are 10cm. find its total surface area?

Answer 1

Given that , 

 The radii of the bottom and top circle are r₁ = 33 cm and r₂ = 27 cm 

 The slant height of the frustum cone 

l = 10 cm

The total surface area of the frustum cone

`S=pi(r_1+r_2)xxl+pi r_1^2+pi r_2^2`

`=22/7xx(33+27)xx10+22/7xx33^2+22/7xx27^2` 

`= 22/7xx600+22/7xx1089+22/7xx729`

`=22/7(600+1089+729)`

`=22/7xx2418`

= 7599.42 cm²

Hence, the total surface area of the frustum cone is 7599.42 cm²