Question

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

• A. 800 $m^2$
• B. 8580 $m^2$
• C. 858 $m^2$
• D. 858 $c{m}^2$

Answer 1

Answer: (C)

858 $m^2$

Given that, a rope by which a cow is tethered is increased from $16m$ to $23m$

To find out: The additional area that the cow can graze now

We know that area of a circle of radius $r=\pi r^2$

$\therefore$ Additional ground area $=\pi \left(\right(23{)}^2-\left(16{)}^2\right)$

$\Rightarrow \frac{22}{7}(529-256)[\because \pi =\frac{22}{7}]$

$\Rightarrow \frac{22}{7}\left(273\right)$

$=858m^2$

Hence, the cow can now graze an additional area of $858m^2$.