document.write( "Question 968186: train A leaves at 3, train B leaves at 8. train B is traveling 120mph faster than train A and passes train A at 10. what speeds are both trains traveling at?
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Algebra.Com's Answer #591706 by Theo(13342)\"\" \"About 
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train A travels for 7 hours from 3 to 10 at x mph.
\n" ); document.write( "train B travels for 2 hours from 8 to 10 at x + 120 mph.
\n" ); document.write( "rate * time = distance.
\n" ); document.write( "when train B catches up to train A, they have both traveled the same distance.
\n" ); document.write( "formula for train A is 7x = d
\n" ); document.write( "formuls for train B is 2(x+120) = d
\n" ); document.write( "simplify to get:
\n" ); document.write( "7x = d
\n" ); document.write( "2x + 240 = d
\n" ); document.write( "subtract second equation from first equation to get:
\n" ); document.write( "5x - 240 = 0
\n" ); document.write( "add 240 to both sides of that equation to get 5x = 240
\n" ); document.write( "divide both sides of the equation by 5 to get x = 48
\n" ); document.write( "train A travels 7 hours at 48 mph for a total of 7 * 48 = 336 miles.
\n" ); document.write( "train B travels 2 hours at (48 + 120) = 160 mph for a total of 168 * 2 = 336 miles.
\n" ); document.write( "train B catches up to train A at the 336 mile mark.
\n" ); document.write( "train A is traveling at 48 mph and train B is traveling at 168 mph.
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