Perimeter of a sector
The perimeter is the distance all around the outside of a shape. We can find the perimeter of a sector using what we know about finding the length of an arc.
A sector is formed between two radii and an arc. To find the perimeter, we need to add these values together.
\(\text{Perimeter = Arc length + 2r}\)
Here, we are given the arc length and the radius.
Substituting these values, we get:
\(\text{Perimeter =}27.5 + (2 \times 45)\)
\(\text{= 27.5 + 90}\)
\(\text{= 117.5 cm}\)
Question
Find the perimeter of this sector.
\(\text{Perimeter =}15 + (2 \times 10)\)
\(\text{= 15 + 20}\)
\(\text{= 35 cm}\)