Question

find the area of circle whose circumference is 22cm​

Answer 1

Answer:

circumference=22 cm

let the radius of circle be r

circumference of circle =2πr

22=2×22/7×r

r=(22×7)/(22×2)

r=154/44

r=3.5

area of circle=πr²

22/7×3.5×3.5

269.5/7

=38.5cm²

Answer 2

$\large\sf \underline{ \underline{ \: Answer : \: \: \: }}$

$\to$ Area of circle = 38.5 cm²

$\large\sf \underline{ \underline{ \: Explaination : \: \: \: }}$

Let ,

The radius of the given circle = r

Given ,

Circumference of circle = 22 cm

We know that ,

$\large\fbox{ \fbox{ \sf Circumference \: of \: a \: circle = 2πr}}$

$\to \sf 22 = 2 × \frac{22}{7} × r</p><p> \\ \\ \to \sf</p><p>r = \frac{22 \times 7}{22 \times 2} \\ \\ \to \sf</p><p></p><p>r = \frac{155}{44} \\ \\ \to \sf</p><p></p><p>r = 3.5 \: cm$

Now ,

$\large\fbox{ \fbox{ \sf Area \: of \: circle = \pi {r}^{2} }}$

$\sf \to Area = \frac{22}{7} × 3.5 × 3.5 \\ \\ \sf \to </p><p></p><p>Area = \frac{269.5}{7} \\ \\ \sf \to </p><p>Area = 38.5 \: \: {cm}^{2}$

$\therefore$The area of the given circle is 38.5 cm²