Question

Find the speed of a bus in kilometre per hour, if its speed is 25 metres per second.

Answer 1

 $1 \mathrm{~m}=\frac{1}{1000} \mathrm{~km}$

and 1 second $=\frac{1}{60 \times 60}$ hour

$\therefore$ Speed of the bus $=\frac{25 \mathrm{~m}}{1 \text { second }}$

$$

\begin{aligned}

=& \frac{25 \times \frac{1}{1000} \mathrm{~km}}{1 \times \frac{1}{60 \times 60} \mathrm{hr}} \\

=& \frac{25}{1000} \times 60 \times 60 \\

=& 90 \mathrm{~km} / \mathrm{h} \text {; Ans. }

\end{aligned}

$$