Question

Find the length of a rope by which a cow must be tethered in order that it may be able to grazean area of 9856 sq.M.?

Answer 1

let the length of rope be r

area gazed by cow =

$\pi {r}^{2}$

(since the cow is fixed to an axis therefore the point at which it has been tethered will act as centre and the rope will act as radius)

$9856 = \pi {r}^{2}$

$9856 \times 7\div 22 = {r}^{2}$

$3136 = {r}^{2}$

$r = \sqrt{3136}$

r = 56 m

Answer 2

See the above attachment

Hope it's helpful