The length of a rope, to which a cow is tied, is increased from $19$ m to $30$ m. How much additional ground will it be able to graze ? Assume that the cow is able to move on all sides with equal ease. Use $\pi = \frac{22}{7}$ in your calculations.
Option B. 1694 sq m
Area of circle = π$r^{2}$
Additional ground will cow be able to graze = Outer circle – Inner circle
= π$30^{2}$ – π$19^{2}$
=$\frac{22}{7}$[900 – 361]
= $\frac{22}{7}$ * 539
= 1694
For detailed solution,
https://edurev.in/question/1497248/The-length-of-a-rope--to-which-a-cow-is-tied--is-increased-from-19-m-to-30-m--How-much-additional-gr