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Flying Around
Assume a red plane leaves from city A to city B and at the same time a blue plane from city B heads toward city A. The wind current is around 5 mph and is traveling against the Blue plane. Both planes are travelling at 120 miles per hour relative to the wind (not the ground). If the distance between the two cities is 300 miles, after how long will the two planes meet?
Answer
Set up 2 equations:distance = rate * time
speed going with the wind = 120 + 5
speed against the wind = 120 - 5
d = (120+5)t
300 - d = (120-5)t
Add the two equations together:
300 = 125t + 115t
300 = 240t
1.25 = t
They will meet in 1.25 hrs.
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