Excluding stoppages, the speed of a train is 55 kmph and including stoppages it is 40 kmph. Of how many minutes does the train stop per hour?
Choices.
A) 82
B) 16
C) 12
D) 82
E) 18

Rationale: "explanation : t = 15 / 55 * 60 = 16 answer : option b"
Answer: B