SOLUTION: <Not sure really which catagory this is in?> Train A and B are traveling in the same direction on parrallel tracks. Train A at 80 miles per hour and train B at 90 miles per hour

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Question 178308:
Train A and B are traveling in the same direction on parrallel tracks. Train A at 80 miles per hour and train B at 90 miles per hour. Train A passes a station at 7:20pm. If train B passes the same station at 7:32pm, at what time will train B catch up to train A?
My answer would be N, not defined becuase they are travling at different speeds. However, train B is going faster than train A. If I had to guess, I would say 8:43pm I'm confused, please help me. Thank you for your help!
Found 2 solutions by ptaylor, josmiceli:
Answer by ptaylor(2198) (Show Source):
You can put this solution on YOUR website!

Distance(d) equals Rate(r) times Time(t) or d=rt; r=d/t and t=d/r
When Train B passes the station, Train A is 12 min or 1/5 hr past the station and this equates to 80*(1/5) mi=16 mi ahead of train B
Let t=time required for Train B to catch train A (counting from 7:32 pm)
Now we know that when the two trains have travelled the same distance, then train B will have caught Train A, so:
90t=16+80t subtract 80t from each side
90t-80t=16+80t-80t collect like terms
10t=16 divide each side by 10
t=1.6 hr=1 hr 36 min-------------------time that elapses before Train B catches Train A
So, 7:32 pm+1 hr 36 min=9:08 pm time that Train B catches Train A
Does this help???------ptaylor

Answer by josmiceli(19441) (Show Source):
You can put this solution on YOUR website!
If the slower train was bhind the faster train,
the slower train would never catch up.
This problem puts the faster train behind the slower
one, so it has a chance to catch up.
7:32 minus 7:20 is 12 minutes. That's the elapsed
time between the slower train passing the station
and the faster train passing it
How far did the 1st train go in that 12 min?
12 min is 12/60 of an hour

mi
So, train A has a 16 mi headstart over B
If I have a stopwatch, and I start it when train B
passes the station, and I'm also able to stop it
when B catches A, They'll both be travelling for the
same length of time, except A is 16 mi closer to
where they're going to meet.
For B:
(1)
For A:
(notice is the same for both)
(2)
Since both are equal to , I'll set the
right sides equal to eachother

hr
This is 1 hr + min
This is the elapsed time since 7:32 when B passed the station
7:32 + 1 = 8:32 and 8:32 + 36 min = 9:08
Train B catches up to train A at 9:08
I'll check my answer:
What's the distance from the station to where they meet?
(1)

mi
(2)
(2)

hr
OK