NIELIT 2017 DEC Scientist B - Section A: 53

Question

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 $\pi$ = 22/7 in your calculations.

• A. $1696$ sq m
• B. $1694$ sq m
• C. $1594$ sq m
• D. $1756$ sq m

Answer 1

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