Subject: mathqa
Question: two trains 160 m and 160 m long run at the speed of 60 km / hr and 40 km / hr respectively in opposite directions on parallel tracks . the time which they take to cross each other is ?
Option: 
A: 10.8 sec
B: 11.52 sec
C: 10.52 sec
D: 14.52 sec
Answer: B