Question

A train 400 m long crosses an electric pole in 32 sec . Find the speed of train in km /hrs

Answer 1

400 m=0.4 km
32 sec= 32/3600=0.0088 hrs
speed =distance/time
speed=0.4/0.0088= 45.45km/hr

Answer 2

Distance Travelled = 400 m = 0.4 km

Time taken = 32 s = 32/3600


Speed = Distance / Time

$speed = \frac{0.4}{ \frac{32}{3600} } km {h}^{ - 1} \\ \\ = \frac{0.4 \times 3600}{32}$

= 45 km/h