The length of a rope in meter by which a cow must be tethered in order that she may be able to graze an area of 2826 sq.m is ?

The cow can graze an area of 2826 sq.m i.e it is able to cover area of circle of 2826 sq.m

Therefore,  $\mathrm{\pi r}2$ =2826
$r2$ =(2826×7/22) = 899.18 = 900
r = 30 m.

Therefore, the radius of the circle implies the length of the rope = 30 mts.