Question

The area of a circle is 61.2cm2.
Find the length of the radius rounded to 2 DP.

Answer 1

4.41 cm

Explanation:

The area of a circle is given by

A = pi r^2

61.2 = pi r^2

Using 3.14 for pi

61.2 / 3.14 = r^2

19.49044586 = r^2

Take the square root of each side

sqrt( 19.49044586) = sqrt(r^2)

4.414798507 = r

To 2 decimal places

4.41 = r