Question

Find the area and perimeter of the following sector :

Radius= 4.2 cm, angle at the centre is 60 ° 

Answer 1

Area of the sector = `(pi "r"^2 xx theta/360^circ)`

`= 22/7 xx 4.2 xx 4.2 xx 60^circ/360^circ`

= 9.24 cm²

Peri meter of the sector

= 2r + `(2 pi "r" xx theta/360^circ)`

`=2 xx 4.2 + (2 xx 22/7 xx 4.2 xx 60^circ/360^circ)`

= 8.4 + 4.4

 = 12.8 cm

Area of the sector = 9.24 cm² and perimeter = 12.8 cm