Question

a bus starts to move with thespeed of 20m/s.calculate the time taken by the bus to cover a distance of 72km.

Answer 1

The Answer is....

Distance = 72km=72000m
Speed = 20m/s

Therefore,

Time taken
= Distance/Speed
=72000/20
=3600seconds
=60 minutes
=1 hour

Hope this helps...

Answer 2

$20 \frac{m}{s} = \frac{18}{5} \times 20 \: \: \: \: \frac{km}{hr} \\ = 18 \times 4 \\ = 72$
now
$time = \frac{distance}{speed} \\ = \frac{72}{72} \\ \\ = 1hr$