The area of the semi-circle is the measure of the amount of surface bounded by the semi-circle. The area of a semi-circle is half of the area of a circle. When a circle is divided into two equal parts, each part is called the area of a semi-circle. The total area of a semi-circle is 180°. On this page, we will discuss the area of a semicircle in detail.

## Table of Contents

## How to find the area of a semi-circle.

The area of an enclosed region (semi-circle) is measured to find the size of a standard unit area that can fit in it. Since the area of a semi-circle is half the area of a circle. The formula for finding the area of a semi-circle is 1/2 × πr^{2}, where π = 22/7 and r = radius of the circle.

let’s understand the area of a semi-circle by working through some examples.

## How to find the area of semi-circle when the radius of the circle is given.

Example 1. If the radius of a circle is 7cm find the area of the semi-circle. [Take π=22/7]

Solution

The area of a semicircle = 1/2 ×πr^{2}, where π = 22/7 and r = 7cm

= 1/2 × 22/7 × 7^{2}

= 1/2 × 22 × 7

= 154/2

= 77cm^{2}

∴ The area of a semi-circle = 77cm^{2}

## How to find the area of a semi-circle when the area of a circle is given.

Example 2. If the area of a circle is 48cm^{2}. Find the area of the semi-circle.

Solution

The area of a semi-circle = 1/2 × πr^{2}, since the area of a circle = πr^{2} = 48cm^{2}

= 1/2 × 48cm^{2}

= 24cm^{2}

∴ The area of a semi-circle = 24cm^{2}