Two trains Janta Express and Bhopal Express are running together in opposite directions at the speed of 36 km/hr and 54 km/hr. The Janta Express crosses a man whose speed is 18 km/hr walking in opposite direction in 20 seconds. The Bhopal Express crosses a pole in 30 seconds. At what time they will cross each other.
1
20 seconds
2
24 seconds
3
25 seconds
4
30 seconds