Question

A circle has a diameter of 42 cm. What would be its circumference ?

• A. 120 cm
• B. 132 cm
• C. 100 cm
• D. 210 cm

Answer 1

The correct option is B 132 cm

We know that the circumference of the circle is given by $2\pi r,$ where $r$ is the radius of the circle.
i.e., $\text{Circumference}=2\pi r=\pi \times \left(2r\right)$
$=\pi \times \text{diameter}$
$=\frac{22}{7}\times 42$
$=132cm$