WBCS.LIVE practice question

A train travelling at constant speed crosses two persons walking in the same direction in 4 seconds and 4.2 seconds, respectively. The first person was walking at the speed of 4.5 km/h while the second was walking at the speed of 6 km/h. What was the speed of the train (in km/h)?

Solve this multiple-choice question and check the correct answer with its explanation below.