11. The radius of a circular field is 20 m. Inside it runs a path 5 m

1.	11. The radius of a circular field is 20 m. Inside it runs a path 5 m wide all around. Find the area of thepath. (Take Ď =-)7
Answer» Area of circular field Af = pirr Given, r = 20 m Then,Af = 22/72020 = 8800/7 Area of inner circle Ai = pi(r - 5)(r - 5) = 22/7(20-5)(20-5) = 22/71515 = 4950/7 Area of circular path= Af - Ai= 8800/7 - 4950/7= 3850/7= 550 m^2

11. The radius of a circular field is 20 m. Inside it runs a path 5 m wide all around. Find the area of thepath. (Take Ď =-)7

Answer»

Area of circular field Af = pi*r*r

Given, r = 20 m

Then,Af = 22/7*20*20 = 8800/7

Area of inner circle Ai = pi*(r - 5)*(r - 5) = 22/7*(20-5)*(20-5) = 22/7*15*15 = 4950/7

Area of circular path= Af - Ai= 8800/7 - 4950/7= 3850/7= 550 m^2