Question

A rectangular sheet of paper $44$ cm $\times 18$ cm is rolled along its length and a cylinder is formed. The volume of the cylinder so formed is equal to $\left(\text{Take}\pi =\frac{22}{7}\right)$:

• A. $2772c{m}^3$
• B. $2506c{m}^3$
• C. $2460c{m}^3$
• D. $2672c{m}^3$

Answer 1

Answer: (A)

If the sheet is rolled along its length then the circumference will be equal to the length of the rectangle.
$\therefore 2\pi r=44$
$\therefore r=\frac{44}{2\times \frac{22}{7}}$
$\therefore r=7$ cm
Also, height of the cylinder will be equal to the breadth of the rectangle.
$\therefore h=18$ cm
$\therefore$ volume of the cylinder $=\pi r^{2}h$
$=\frac{22}{7}\times 7^2\times 18$
$=2772$ $c{m}^3$