Question

Kylie drew a circle with a diameter of 8 cm. Paige drew a circle with a radius of 3 cm. Approximately how much larger is the area of Kylie’s circle than the area of Paige’s circle? Use 3.14 for pi and round to the nearest whole number.

Answer 1

22 sq. cm.

Explanation:

Area of a circle is

`A=\pi r^2`

where, r is radius of the circle.

Diameter of Kylie's circle = 8 cm

Radius of Kylie's circle = 8/2 = 4 cm

Radius of Paige's circle = 3 cm

Area of Kylie's circle is

`A_1=\pi (4)^2=(3.14)(16)=50.24\text{ sq. cm}`

Area of Paige's circle is

`A_2=\pi (3)^2=(3.14)(9)=28.26\text{ sq. cm}`

Difference between the areas is

`A_1-A_2=50.24-28.26=21.98\approx 22\text{ sq. cm}`

Therefore, the area of Kylie’s circle is 22 sq. cm larger than the area of Paige’s circle.

Answer 2

The area for a circle with a diameter of 8 cm is 50.24 cm². The area of a circle with a radius of 3 cm is 28.26 cm². 50.24 - 28.26 =  21.98 cm. So the difference is 21.98 cm.