Question

Calculate the perimeter of the sector.

138°
0
11 mm
Give your answer correct to 1 decimal place.
mm

Answer 1

To find the perimeter of a sector, we need to know the radius and the angle of the sector.

We are given that the angle of the sector is 138°. We also need to know the radius of the sector in order to calculate the perimeter.

We are not given the radius of the sector, so we cannot calculate the perimeter.

Answer 2

Answer: 48.5 mm

Explanation:

Perimeter means length of all the lines.

The 2 lines on bottom = 11mm

to find the length of the arc:

Formula: proportion of angle*Circumference

`arc = (angle)/(360) 2\pi r`

`arc = (138)/(360) 2\pi (11)`

arc = 26.5

Add all sides for perimeter:

P = arc + r + r

P = 26.5 + 11 + 11

P = 48.5 mm