Question

the area enclosed between the concentric circles 770cm

Answer 1

area of outer circle=πr^2
=22/7 multiply 21x21
=66x21=1386cm square
area enclosed between circles =770 cm square
so area of inner circle =1386-770=616 cm square
area of inner circle =πr^2=22/7 multiply r^2
616x7/22=r^2
4312/22=r^2
392/2=r^2
196=r^2
r=14 cm

Answer 2

Answer:

hope this helps you.....