Question

A Joker's cap is in the form of a right circular cone of base radius 7 cm and height 27 cm. Find the area of the sheet required to make 10 such caps.

Answer 1

Given Radius $=7$ cm and height $=27$ cm

Then slant height l=$\sqrt{(27{)}^2+(7{)}^2}=\sqrt{729+49}=\sqrt{778}=27.84$ cm

Then curved surface area conical cap = $\pi \times r\times l=\frac{22}{7}\times 7\times 27.84=612.48m^2$

Then sheet required for make 10 caps = $612.48\times 10=6124.8m^2$