Problema Solution
Train A leaves the station traveling at 50 miles per hour. Four hours later, Train B leave the same station traveling in the same direction at 60 miles per hour. How long does it take train B to catch up to train A?
Answer provided by our tutors
let
v1 = 50 mph the speed of train A
t1 = the time that train A is traveling
v2 = 60 mph the speed of train B
t2 = the time that train B is traveling
4r hours later, Train B leave the same station...
t1 = t2 + 4
since speed = distance/time => distance = speed*time
both train will travel the same distance before meeting thus we have
v1*t1 = v2*t2
50t1 = 60t2
by solving the system of equations
t1 = t2 + 4
50t1 = 60t2
we find
t1 = 24 h
t2 = 20 h
click here to see the step by step solution of the system of equations
it took 20 hours for the train B to catch up to train A.