Question

"Find the area of the larger circle if the circumference of one of the smaller circles is 36 pi mm.

"

Answer 1

The area of the larger circle is 4069.44 millimeter square.

Explanation:

Given : The circumference of one of the smaller circles is 36 pi mm.

To find : The area of the larger circle?

Solution :

Circumference of the smaller circle is
`C=36\pi`

Circumference of circle is
`C=2\pi r`

Substitute the value,

`36\pi=2\pi r`

`r=18`

The radius of smaller circle is 18 mm.

The radius of larger circle is twice the radius of smaller circle.

Radius of the larger circle, R= 2(r)=2(18)=36 mm

Area of the larger circle is
`A=\pi R^2`

`A=\pi 36^2`

`A=1296\pi`

`A=4069.44mm^2`

Therefore, The area of the larger circle is 4069.44 millimeter square.

Answer 2

C ( smaller ) = 36 π mm
2 r π = 36 π / : π
2 r = 18 mm
Radius of the larger circle: r = 2 · 18 = 36 mm
A = r² π = 36² π = 1296 π mm²
Answer: area of the larger circle is 1296 π mm².