Question

The perimeter of a circle and its diameter vary _______ with each other.

Answer 1

Relation between the perimeter and the diameter of the circle.

The perimeter or circumference of the circle is given by a formula,

$$\begin{gathered} \mathrm{Perimeter}=2\mathrm{\pi }r \\ =\mathrm{\pi }d\left[\because d=2r\right] \end{gathered}$$

Where $d$ is the diameter and $r$ is the radius of the circle.

From the above relation, it is observed that the perimeter and diameter of the circle are directly related.

Hence, the perimeter of a circle and its diameter vary directly with each other.