SOLUTION: A train leaves Boston at 3:00 pm and heads for new york at 35 mph. At the exact same time, another train leaves new york and heads for Boston at a speed of 45 mph. If the distance

Algebra ->  Equations -> SOLUTION: A train leaves Boston at 3:00 pm and heads for new york at 35 mph. At the exact same time, another train leaves new york and heads for Boston at a speed of 45 mph. If the distance       Log On


   

Question 923359: A train leaves Boston at 3:00 pm and heads for new york at 35 mph. At the exact same time, another train leaves new york and heads for Boston at a speed of 45 mph. If the distance between new york and Boston is 240 miles, how long will it be before the trains meet?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Think of this as one train standing still and
the other moving at the sum of their speeds
Let +t+ = time in hrs until they meet
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+240+=+%28+35+%2B+45+%29%2At+
+240+=+80t+
+t+=+3+
They will meet in 3 hrs at 6 PM
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check:
+d%5B1%5D+=+35%2A3+
+d%5B1%5D+=+105+ mi
and
+d%5B2%5D+=+45%2A3+
+d%5B2%5D+=+135+ mi
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+d%5B1%5D+%2B+d%5B2%5D+=+240+
+105+%2B+135+=+240+
+240+=+240+
OK