Question

A square sheet of side $28$ cm is folded into a cylinder by joining its two sides. Find the base area of the cylinder thus formed (in $c{m}^2$).

• A. $\frac{524}{11}$
• B. $\frac{575}{11}$
• C. $\frac{629}{11}$
• D. $\frac{686}{11}$

Answer 1

The correct option is D $\frac{686}{11}$

As the square sheet is folded to form a cylinder, circumference of the base of the cylinder will be equal to $28$ cm

Let $R$ be the radius of the cylinder
Circumference of base of cylinder $=2\pi R$
So, $2\times \frac{22}{7}\times R=28$
$\Rightarrow R=\frac{49}{11}$
And area of the base of the cylinder $=\pi R^2$

$=\frac{22}{7}\times \frac{49}{11}\times \frac{49}{11}$

$=\frac{686}{11}$ sq.cm