Circumference of a circle is the measure of the length of the circle.
Circumference of a circle = 2πr
How to find circumference of a circle when radius is given
Question 1
Find the circumference of a circle of radius 7 cm?
Explanation
The radius of given circle is r = 7 cm
Circumference of the circle = 2πr
= ( 2 x 22/7 x 7 ) cm
= 44 cm
Question 2
Find the circumference of a circle of radius 28 cm?
Explanation
The radius of given circle is r = 28 cm
Circumference of the circle = 2πr
= ( 2 x 22/7 x 28 ) cm
= 176 cm
Question 3
Find the circumference of a circle of radius 49 cm?
Explanation
The radius of given circle is r = 49 cm
Circumference of the circle = 2πr
= ( 2 x 22/7 x 49 ) cm
= 308 cm
Question 4
Find the circumference of a circle of radius 3.5 cm?
Explanation
The radius of given circle is r = 3.5 cm
Circumference of the circle = 2πr
= ( 2 x 22/7 x 3.5 ) cm
= 22 cm
How to find circumference of a circle when diameter is given
Question 1
Find the circumference of a circle, whose diameter is 14 cm?
Explanation
The diameter of given circle = 14 cm
Then,
= 14/2 cm = 7 cm
Circumference of circle = 2πr
= ( 2 x 22/7 x 7 ) cm
= 44 cm
Question 2
Find the circumference of a circle, whose diameter is 56 cm?
Explanation
The diameter of given circle = 56 cm
Then,
= 56/2 cm = 28 cm
Circumference of circle = 2πr
= ( 2 x 22/7 x 28 ) cm
= 176 cm
Question 3
Find the circumference of a circle, whose diameter is 140 cm?
Explanation
The diameter of given circle = 140 cm
Then,
= 140/2 cm = 70 cm
Circumference of circle = 2πr
= ( 2 x 22/7 x 70 ) cm
= 440 cm
Question 4
Find the circumference of a circle, whose diameter is 98 cm?
Explanation
The diameter of given circle = 98 cm
Then,
= 98/2 cm = 49 cm
Circumference of circle = 2πr
= ( 2 x 22/7 x 49 ) cm
= 308 cm