SOLUTION: Please mail me this answer..asap Train A is heading north to south at a speed of 40 miles per hour. Train B is heading south to north at a speed of 50 miles per hour. A and B ar

Algebra ->  Customizable Word Problem Solvers  -> Travel -> SOLUTION: Please mail me this answer..asap Train A is heading north to south at a speed of 40 miles per hour. Train B is heading south to north at a speed of 50 miles per hour. A and B ar      Log On

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Question 868986: Please mail me this answer..asap
Train A is heading north to south at a speed of 40 miles per hour. Train B is heading south to
north at a speed of 50 miles per hour. A and B are traveling toward each other on
neighboring tracks and the distance between them is 180 miles and there are no stations
between them. A bird is flying back and forth between them at a speed of 55 miles per hour.
The bird will keep flying until the trains cross each other. What is the distance traveled by the bird before the crossing happens?
a) 180 miles
b) 110 miles
c) 135 miles
d) 90+ 90/2+90/4+90/6….. miles

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Train A is heading north to south...
That's heading south.
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Going in opposite directions, the speeds are added, often called the "closing speed."
40 + 50 = 90 mi/hr
d = r*t
t = d/r = 2 hours until they meet
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The bird flies for 2 hours at 55 mi/hr