Question

A conical tomb is to be covered with metal strips of area 5 m${}^2$ each. The slant height and radius of the tomb are measured to be 35 m and 8 m respectively. Find the total number of strips used to cover the tomb. (Take $\pi =\frac{22}{7}$)

• A. 126
• B. 176
• C. 150
• D. 160

Answer 1

The correct option is B 176

Given,
Area of metal strips$=5m^2$
Slant height of the conical tomb, $l=35m$
Radius of the conical tomb, $r=8m$

$\therefore$ Curved surface area of the tomb $=\pi rl$
$=\frac{22}{7}\times 8\times 35$
$=880m^2$

$\therefore$ Number of metal strips required
$=\frac{\text{Curved surface area of tomb}}{\text{Area of metal strips}}$

$=\frac{880m^2}{5m^2}$

$=176$ strips