##### Definition:

A sector angle is a plane figure surrounded by two radii and the included arc in a circle.
A sector comprising of the central angle of 180° is known as a semicircle.
This tutorial explains you how to calculate the degree measure of sector in a circle.

#### Formula:

Angle of sector = (A x 360) / π r^{2}
###### Where

A = area of sector
r = radius of sector
##### Example :

Consider a cake which has a radius of 5 m. When a piece of cake is cut from it which has an area of 50 m then calculate the angle made by the piece of cake.

##### Solution:

Angle of sector | = (A x 360) / π r^{2} |

| = (50 x 360) / π x 5 x 5 |

| = 18000 / 78.5 |

| = 229.299° |