Find the circumference of the circles from their radii given below.

(1) 56 cm

(2) 7.7 cm

(3) 2.8 m

(1). Given: Radius, r = 56 cm

We have

Circumference of the circle is given by,

Circumference = 2πr

⇒ Circumference

⇒ Circumference

Hence, circumference is 352 cm.

(2). Given: Radius, r = 7.7 cm

We have

Circumference of the circle is given by,

Circumference = 2πr

⇒ Circumference

⇒ Circumference

Hence, circumference is 48.4 cm.

(3). Given: Radius, r = 2.8 m

We have

Circumference of the circle is given by,

Circumference = 2πr

⇒ Circumference

⇒ Circumference

Hence, circumference is 17.6 m.