Question

The ratio of circumference and area of a circle is $2:7$. Find its circumference ?

• A. $14\pi$
• B. $\frac{7}{pi}$
• C. $7\pi$
• D. $\frac{14}{pi}$

Answer 1

The correct option is A $14\pi$

$\frac{Circumference}{Area}=\frac{2}{7}$

$\frac{2\Pi r}{\Pi r^2}=\frac{2}{7}$

$\frac{2}{r}=\frac{2}{7}$

$r=7cm$

$Circumference=2\Pi r=2\ast \pi \ast 7=14\pi cm$