Question

find the perimeter and area of each of the following shape ​

Answer 1

Given:

A semi circle with

• Diameter = 14 cm

What To Find:

We have to find the perimeter and area of the semi circle.

Solution:

• Finding the perimeter

Using the formula,

⇒ $\sf{Perimeter = \dfrac{1}{2} (\pi d) + d}$

Substitute the values,

⇒$\sf{Perimeter = \dfrac{1}{2} \times \dfrac{22}{7} \times 14 \: + 14}$

Cancel 2 and 22 and 7 and 14,

⇒ $\sf{Perimeter = 11 \times 14 + 14}$

Multiply 11 by 14,

⇒ Perimeter = 154 + 14

Add 154 and 14,

⇒ Perimeter = 168 cm

• Finding the area

Using the formula,

⇒ $\sf{Area = \dfrac{1}{2} (\pi r^2)$ - where radius = half of diameter = 14/2 = 7 cm

Substitute the values,

⇒ $\sf{Area = \dfrac{1}{2} \times \dfrac{22}{7} \times 7 \times 7}$

Cancel 2 and 22 and 7 and 7,

⇒ $\sf{Area = 11 \times 7}$

Multiply 11 by 7,

⇒ Area = 77 cm²

∴ Therefore the perimeter and the area of the circle are 168 cm and 77 cm² respectively.

Formula Used:

→ $\sf{Perimeter = \dfrac{1}{2} (\pi d) + d$

→ $\sf{Area = \dfrac{1}{2} (\pi r^2)$

Answer 2

Given:

A semi circle with

• Diameter = 14 cm

What To Find:

We have to find the perimeter and area of the semi circle.

Solution:

• Finding the perimeter

Using the formula,

$⇒ \sf{Perimeter = \dfrac{1}{2} (\pi d) + d}$

Substitute the values,

$⇒ \sf{Perimeter = \dfrac{1}{2} \times \dfrac{22}{7} \times 14 \: + 14}$

Cancel 2 and 22 and 7 and 14,

$⇒ \sf{Perimeter = 11 \times 14 + 14}$

Multiply 11 by 14,

ANSWER

⇒ Perimeter = 154 + 14