Question

The circumference of a circular plot is 220 m. A 14 cm wide concrete track runs around outside the plot. Find the area of the track.Use π = 22/7​

Answer 1

circumference of circular plot=220cm
2 x 22/7 x r=220
r=35m
now
area of circular track=pi. {R^2-r^2}
where R=35m+14m=49m
and r=35m
now area of track=22/7 x {(49)^2-(35)^2}
=22/7 x 14 x 84 m^2
=3696 m^2

Answer 2

let the radius of the circular plot be x
circumference = 220
2 x 22/7 x x = 220
x = 35
Now
new radius = 35+ 14 =49m
area = 22/7(49^2-35^2)
=3696 [approx]