SOLUTION: Two trains are 440 miles apart, and their speeds differ by 12 mph. Find the speed of each train if they are traveling toward each other and will meet in 4 hours. Thank you

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Question 976403: Two trains are 440 miles apart, and their speeds differ by 12 mph. Find the speed of each train if they are traveling toward each other and will meet in 4 hours.
Thank you

Found 2 solutions by josgarithmetic, ikleyn:
Answer by josgarithmetic(39618) About Me  (Show Source):
You can put this solution on YOUR website!
Let one of the trains have the speed of r.
RT=D is how rate, time, distance are related for uniform travel rates.

__________________rate___________time_________distance
__________________r______________4_____________(____)
__________________r+12___________4_____________(____)
Total__________________________________________440

Fill the missing cells, form the necessary equation, and solve.

Answer by ikleyn(52794) About Me  (Show Source):
You can put this solution on YOUR website!

Let  x  be the speed of faster train  (mi/h),  and  y  be the speed of the other train (mi/h).  Then you have the system of two linear equations in two unknowns

x+%2B+y = 440%2F4 = 110,
x+-+y = 12.

To solve the system,  first add both equations.  You will get

2x = 110%2B12 = 122.

Hence,  x = 122%2F2 = 61 mi%2Fh.

Now,  substitute the found value of  x  into the first equation.  You will get

61+%2B+y = 110.

Hence,  y = 110+-+61 = 49 mi%2Fh.

Answer.  The speed of the faster train is  61 mi%2Fh.  The speed of the other train is  49 mi%2Fh.