Question

A tent of height $77dm$ is in the form of a right circular cylinder of diameter $36m$ and height $44dm$ surmounted by a right circular cone. Find the cost of the canvas at Rs. $3.50$ per $m^2$ (Use $\pi =22/7$)

Answer 1

Given total height of the tent as $7.7m$ and length of cylindrical part as $4.4m$

Hence , the height of the cone part $=7.7-4.4=3.3m$

$r=18m$ for both Cylinder and cone

The area of canvas required=Surface area of Cylindrical and cone parts of tent

$A=2\pi rh+\pi r\left(\sqrt{h^2+r^2}\right)$

$A=2\pi \times 18\times 4.4+\pi \times 18\left(\sqrt{{18}^2+{3.3}^2}\right)$

$A=1352.5m^2$

Cost of canvas=$1352.5\times 3.5=5363.6rupees$