Question

The adjoining figure shows the measures of a Joker’s dap. How much cloth is needed to make such a cap?

Answer 1

Given: For the conical cap, 

radius (r) = 10 cm, 

slant height (l) = 21 cm 

To find: Cloth required to make the cap. 

Cloth required to make the cap  = Curved surface area of the conical cap 

= πrl = 22/7 × 10 × 21 

=22 × 10 × 3 

= 660 cm² 

∴ 660 cm² of cloth will be required to make the cap.