There is a path of uniform width 7 m round and outside a circular garden of diameter 210 m. Find the area of the path.
Diameter =210 m
Radius of inner circule r2=105m
Width =7m
Radius of outer circle r1=105+7=112m
∴ Area of path =πr21−πr22
=π[r21−r22]
=227(r)1+r2)(r1+r2)
=227(112+105)
(112-105)
=227×217×7
=4774m2