Question

bus travels at the speed of 72 kilometre per hour how much time will it take to cover 400 meters

Please help ​

Answer 1

Short Answer: 20 seconds

Long Answer:

First Convert 72 km/hr to m/s

72×1000/(60×60) = 20 m/s

Time to cover 200 m bridge = 200 m/(20 m/s) => 10 s

Since length of the train is 400 m, the bridge can only hold half the length of the train. So the other half will take another 10 s.

So, 10 s + 10 s = 20 s

This is the simplest understandable solution and there are many ways to do it.

Note: This solution is not recommended for exams as it wastes precious time explaining everything.