Question

A joker’s cap is in the form of right circular cone of base radius 7 cm and height 24 cm. Find the area of the sheet required to make 10 such caps.

`["Assume "pi=22/7]`

 

Answer 1

Radius (r) of conical cap = 7 cm

Height (h) of conical cap = 24 cm

Slant height (l) of conical cap = `sqrt(r^2+h^2)`

= `[sqrt((7)^2+(24)^2)] cm`

= `sqrt (576 + 49)  cm`

= `sqrt625  cm`

= 25 cm

Curved surface area of 1 conical cap = πrl

= `(22/7xx7xx25)cm^2`

= 550 cm²

Curved surface area of 10 such conical caps = (10 × 550) cm² = 5500 cm²

Therefore, the required area of the sheet is 5500 cm².