Question

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

Answer 1

here,
r=7 & h=27
as we know that cap is open at one side

therefore area of sheet required to make =10×c.s.a
of the cone

so c.s.a = πrl (1)
but l=?
let's find
as we know l^2=r^2+h^2
tjerefore. l= √r^2+h^2
l= √7^2+27^2
l=√49+729
l=√778
l= 27.9(approx)
now apply this in (1) and find the answer