Question

How long will a man take to make a round of circular field of radius $12m$, cycling of speed of $8km/hr$.

Answer 1

$Time=\frac{Circumference}{speed}$

$\Rightarrow$ Circumference $=2\times \frac{22}{7}\times \frac{12}{1000}km=\frac{66}{875}km$

$\Rightarrow$ Time $=\frac{66}{875}\times \frac{1}{8}=\frac{33}{3500}hrs$

$=\frac{33}{3500}\times 3600sec$

$=33.94sec.$

Hence, the answer is $33.94sec.$