Question

A rectangular box of metal $12$ cm x $15$ cm rolled along its length and a cylinder is formed. Find the volume of the cylinder. (Use $\pi =\frac{22}{7}$).

• A. $180.18c{m}^3$
• B. $170.18c{m}^3$
• C. $160.18c{m}^3$
• D. $150.18c{m}^3$

Answer 1

Answer: (B)

$170.18c{m}^3$

Let height $h$ of the cylinder be $15$ cm
Circumference of the base $=2\pi r$
2$\pi r=12$
$2\times \frac{22}{7}\times r=12$
$44\times r=12\times 7$
$r=1.9$
Therefore, volume of the cylinder $=\pi r^{2}h$ $=\frac{22}{7}\times {1.9}^2\times 15$

$=170.18c{m}^3$