Question

A military tent of height 8.25 m is in the form of a right circular cylinder of base diameter 30 m and height 5.5 m surmounted by a right circular cone of same base radius. Find the length of canvas used in making the tent, if the breadth of the canvas is 1.5 m.

Answer 1

Height of the cone = 8.25 - 5.5= 2.75 m
Slant height of the cone(l)= $\sqrt{h^2+r^2}$ = 15.25 m
Surface area of cone= $\pi \times r\times l$ = 3.14 x 15 x 15.25 = 718.3 $m^2$
Surface area of cylinder = 2$\pi \times r\times h$ = 2 x 3.14 x 15 x 5.5
= 518.1 $m^2$
Area of canvas used = 718.3 $m^2$ + 518.1 $m^2$ =1236.4 $m^2$
Length of canvas = $\frac{1236.4}{1.5}$= 824.3 m