SOLUTION: Express commuter train #12 leaves the downtown station and travels at an average speed of 55 miles per hour towards the north side station, which is15.5 miles away. Twelve minutes
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-> SOLUTION: Express commuter train #12 leaves the downtown station and travels at an average speed of 55 miles per hour towards the north side station, which is15.5 miles away. Twelve minutes
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Question 768640: Express commuter train #12 leaves the downtown station and travels at an average speed of 55 miles per hour towards the north side station, which is15.5 miles away. Twelve minutes later, express commuter train #7 leaves the north side station and travels at an average speed of 35 miles per hour towards the downtown station.
At the moment when the two trains pass each other, how far (in miles) is the #12 train from the downtown station and how long (in minutes) has the #12 train have been traveling?
If the answer is not an integer, enter it as an exact decimal.
#12 train is ____________ miles from the downtown station and has been traveling for ____________ minutes.
You can put this solution on YOUR website! How far does #12 get in 12 min? ( I converted 12 min to hrs ) mi
The trains are now mi apart
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Start a stopwatch when #7 leaves
Let = time ( in hrs ) on stopwatch when they meet
Let = distance #7 has to travel until they meet
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#7's equation:
(1)
#12's equation:
(2)
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Substitute (1) into (2)
(2)
(2)
(2) hrs
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(1)
(1) mi
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To find how far #12 is from where it started,
add it's head start to distance after the
stopwatch was started
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#12 is 13.75 mi from the downtown station
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#12 has been traveling for the 11 min head start plus ( convert hrs to min )
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#12 has been traveling for 14 min
