Question

the radius of a sector is 21 cm and it central angle is 120 find the perimeter of sector​

Answer 1

answer

44

explanation

circumference=2×(22/7)×r

here,r=21

so,circumference=44/7×21

=132

c of sector=(angle/360)×total c

=(120÷360)×132

=132÷3

=44

Answer 2

$perimeter \: = \frac{theta}{360} \times 2\pi \: r$

$peimeter = \frac{120}{360} \times 2 \times 3.14 \times 21$

$perimeter = \frac{1}{3} \times 21 \times 6.28$

$perimeter = 7 \times 6.28$

$perimeter = 43.96 \: \: cm$