Question

Find the circumference and area of a circle with radius 7 cm. Express your answer in terms of π.

Answer 1

Circumference = 2πr=2×

7

22

​

×7=44 cm

Area = πr

2

=

7

22

​

×7×7=154 cm

2

Answer 2

With a circle with radius 7 cm, the circumference of given circle is 14π (cm) and the area is 49π (cm²).

Explanation:

Given: radius = 7 cm

Circumference of a circle: C = 2πr

C = 2πr

Substitute given value radius.

C = 2π(7)

Multiply 7 and 2.

C = 14π cm.

Area of a circle: A = πr²

A = πr²

Substitute given value radius.

A = π(7)²

Square the 7.

A = 49π cm²