Question

5. Find the area of a circular ring whose inner and outer radii are 16 cm and 19 cm respectively.​

Answer 1

Answer:

Let us given R=19 cm & r=16 cm

Area of outer circle =π(19)

2

=

7

22

×361

Area of inner circle =π(16)

2

=

7

22

×256

∴ area of the ring =

7

22

×361−

7

22

×256

=

7

22

(361−256)

=

7

22

(105)

=330 cm

2