Question

The circumference of a circle is `12pi`cm. How do you find the a) Diameter: b) Radius: c) Area of the circle in terms of `pi`?

Answer 1

(a) Diameter is `12` `cm`; (b) radius is `6` `cm`; and (c) area is `36pi` `cm^2`.

Explanation:

If `r` is the radius of a circle, then its circumference is `2pir` and area is `pir^2`.

As circumference is given to be `12pi`, we have

`2pir=12pi`

or `r=(12pi)/(2pi)=6` `cm.`

As such radius is `6` `cm` and diameter being double of radius, diameter is `2xx6=12` `cm.`

and area is `pixx6^2=36pi` `cm^2`.