Question 454861
Trains A and B are traveling in the same direction on parallel tracks.
Train A is traveling at 100 mph and train B is traveling 110 mph.
 Train A passes a station at 11:15am.
 If train B passes the same station at 11:27am at what time will train B catch up to train A?
:
From the given information, we know that Train B is 12 min behind A at at 11:15 pm
therefore Train B is:
{{{12/60}}} * 110 = 22 miles behind Train A at that time.
:
Let t = time required for Train B to catch Train A
:
Write a distance equation; dist = speed * time
:
Train B dist = Train A dist + 22 mi
110t = 100t + 22
110t - 100t = 22
10t = 22
t = {{{22/10}}}
t = 2.2 hrs for B to catch A 
:
Convert 2.2 hrs to hrs and minutes: 2 + .2(60) = 2 hr 12 min
:
Find the time from 11:15 pm:
11:15 + 2:12 = 1:27 pm, Train B catches Train A
:
:
We can check this by using relative speed between the trains, which is 10 mph
How long to cover 22 mi at 10 mph? {{{22/10}}} 2.2 hrs which is 2 hrs 12 min