Question

If the diameter of a circle is 20 , what is the area ?

Answer 1

the diameter of a circle is 20

The radius of circle is the half of the diameter of the circle :

Radius = Diamter/2

In the given question , we have Diameter = 20

So,

Radius = 20/2

Radius = 10

The expression for the radius 'r' of the circle is express as :

`\text{ Area of Circle =}\Pi(radius)^2`

Substitute the value of Radius r = 10 in the expression of the area of circle:

`\begin{gathered} \text{ Area of Circle =}\Pi(radius)^2 \\ \text{ Area of Circle =}\Pi(10)^2 \\ \text{ Area of Circle =}3.14*10*10 \\ \text{ Area of Circle =}3.14*100 \\ \text{ Area of Circle =}314 \end{gathered}`

Area of the circle is 314

Answer : 314 unit square.