Excluding stoppage station, the speed of a train is 60 km/h and including stoppages stations it travels at a speed of 45 km/h. For how many minutes does the train stop per hour?

Correct option is D

Given:

Excluding stoppage station, the speed of a train is 60 km/h and including stoppage station it travels at a speed of 45 km/h.

Formula used:

Time × Speed = Distance

1 hour = 60 minutes

Solution:

Let the distance be D

So, the time required to cover the distance without stoppage will be = ($$\frac{D}{60}$$​) hours

Time required for the same distance to cover with stoppage  = ($$\frac{D}{60}$$​) hours

Then, the train stop for $$\frac{D}{45} - \frac{D}{60}$$​ hours =>$$\frac{D}{180}$$​ hours

So,

the stoppage time of the train per hour

= $$\frac{D}{180} ÷ \frac{D}{45}$$​ hours

=> $$\frac{1}{4 }$$​hours

=> ($$\frac{1}4$$​ × 60) minutes

=> 15 minutes

Thus, for 15 minutes the train stops per hour.