Question

A rope by which a cow is tethered is increased from 16 m to 23 m. How much additional ground does it have now graze?

Answer 1

r₁ = 16 m
r₂ = 23 m

Amount of additional ground available = Area of the bigger circle -- Area of the smaller circle

`= π (r_1^2 - r_2^2)`

=  π (23² - 16²)

= π (23 + 16)(23-26)

= 858 m²