Question 192831: Trains A and B are traveling in the same direction on parallel tracks. Train A is traveling at 80 miles per hour and train B at 100 miles per hour. Train A passes a station at 12:25 P.M. If train B passes the station at 12:37 P.M., at what time will train B catch up to train A?
When will Train B catch up to Train A ?
Answer by bhayzone(8)   (Show Source):
You can put this solution on YOUR website! Ans: 1.25 pm
Let.
D = distance from Station A, at which both trains meet.
Train B passes Station A - 12 mins after Train A
In 12 mins Train A has travelled 16 miles.
So, when Train B is at Station A
Train A has travelled 16 miles ahead. The distance remaining is D - 16
Time taken by Train B (t2) to reach meeting point is same as time taken by Train A (after a 16 mile lead)to reach meeting point.
t1 = (D-16) / 80 (Train A has a lead of 16 miles)
t2 = D/100
since t1 = t2
80D = 100(D-16)
8D = 10D - 160
D = 80
Train B can complete 80miles in 80*60/100 = 48 mins.
Thus the trains meet at time 12.37 PM + 48 mins = 1.25 PM
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