Question

The sector of a circle has a radius of 21 cm and centre angle 135°. Find its perimeter?

Answer 1

135/180×22/7×21=99/2=49.5

Answer 2

Answer:

110.53 cm

Step-by-step explanation:

The sector of a circle has a radius of 21 cm and centre angle 135°

Length arc = $2 \pi r \times \frac{\theta}{260}$

Length arc = $2 \times \frac{22}{7} \times 21 \times \frac{135}{260}$

Length arc = $68.53$ cm

Perimeter of sector = Length of arc + 2r

Perimeter of sector = 68.53+2(21)=110.53 cm

Hence the perimeter of sector is 110.53 cm