SOLUTION: Trainsa a and b are traveling in the same direction on parallel tracks. Train a is traveling at 60mph and train b is traveling at 70mph. train a passes the station at 12:10p.m. If

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Question 147179: Trainsa a and b are traveling in the same direction on parallel tracks. Train a is traveling at 60mph and train b is traveling at 70mph. train a passes the station at 12:10p.m. If train b passes the same station at 12:22p.m., at what time will train b catch up to train a.
Found 2 solutions by ankor@dixie-net.com, josmiceli:
Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website!
Trains a and b are traveling in the same direction on parallel tracks. Train a is traveling at 60mph and train b is traveling at 70mph. train a passes the station at 12:10p.m. If train b passes the same station at 12:22p.m., at what time will train b catch up to train a.
:
When train a is at the station, train b is 12 min from the station
Therefore: 70 * = 14 mi is the dist b is from the station, (& 14 mi behind train a)
:
Their relative speed is 70 - 60 = 10 mph
:
How long will it take to cover 14 mi at 10 mph? Time = dist/speed
time = = 1.4 hrs; which is 1 hr + .4(60) = 1 hr 24 min
:
Train b catches up with a: 12:10 pm + 1:24 = 1:34 pm

Answer by josmiceli(19441) (Show Source):
You can put this solution on YOUR website!
Assume I have a stopwatch and I'm on train b
I'm in contact by cellphone with the station
They tell me that train a went by at 12:10.
Then I pass the station at 12:22, and I start my stopwatch
minutes went by, or hr
I know that train a travels at 60 mi/hr

mi
That's how far train a has gone ahead of me
I'm going to press the stopwatch again when the trains meet.
Let = the distance I (train b) will have gone in that time
Then will be the distance that train a has gone.
I can write

Substitute the 2nd equation in the 1st

hr
or 1 hr 12 min
This is 1 hr 12 min past 12:22 when I started the stopwatch, or
13:34, which is 1:34 PM