Question

train A and B are traveling in the same direction on parallel tracks. train A is going 80 miles per hour train B is going 84 miles per hour. train A past a station at 2:15 am train B passes at 2:45 am what time will train B catch train A

Answer 1

In order to catchup, train B must travel the same distance; but its' time must be 1/2 hour less:

Train A time = t hrs,
Train B time = (t - 0.5) hrs.

d2 = d1,
84(t - 0.5) = 80t,
84t - 42 = 80t,
84t - 80t = 42,
4t = 42,
t = 42/4 = 10.5 hrs,
(t - 0.5) = 10.5 - 0.5 =10h to catchup.