Question

Find the diameter of circle whose circumference is 22cm

Answer 1

hey...

circumference of a circle =
$2\pi \: r$
22 cm= 2 × 22/7 × r

22 × 7 /22× 1/2 = r

3.5 = r

diameter = 2 ×radius
.................= 2 ×3.5
...............7 cm

Answer 2

Given,

The circumference of the circle = 22 cm

To find,

The diameter of the circle.

Solution,

The diameter of the circle will be

We can easily solve this problem by following the given steps.

We know that the formula to find the circumference of the circle is the following:

Circumference of the circle (C) = 2πr where r is the radius of the circle

According to the question,

The circumference of the circle = 22 cm

2πr = 22

2×22/7×r = 22 (Putting the value of π to be 22/7)

Using the cross multiplication method,

(2×22×r) = (22×7)

r = (22×7)/(2×22) [(2×22) was in the multiplication on the left-hand side. So, it is in the division on the right-hand side.]

r = 7/2

r = 3.5 cm

We know that diameter of the circle is twice that of its radius.

Diameter (d) = 2×r

d = 2×3.5

d = 7 cm

Hence, the diameter of the circle is 7 cm.