Question

If the diameter of a circle is 28.9 m, what is the area?

Answer 1

The area of a circle with radius `r` is

`S=pi*r^2`

but the diameter `d` is `d=2r=>r=d/2`

hence

`S=pi*(d^2/4)`

where `pi=3.14` and `d=28.9m`