the outer edge of a circular track is 440 m long.if is widened by 5m all around,find the cost of widening it at rate of 8 rs per m square?

Answer 1

2 pi Rin = 440
Rin = 70
Rout = 75

A = pi Rout^2 - pi Rin^2
= 2278 m^2

2278 * 8 = 18221

Answer 2

18212 answer