Question 926526: I'm having some trouble setting up an equation for this word problem.
Two planes start from the same airport and fly in opposite directions. The second plane starts 1/2 hour after the first plane, but its speed is 56 kilometers per hour faster. Find the ground speed of the first plane if 1 hour after the first plane deports the planes are 2670 kilometers apart.
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! Two planes start from the same airport and fly in opposite directions. The second plane starts 1/2 hour after the first plane, but its speed is 56 kilometers per hour faster. Find the ground speed of the first plane if 1 hour after the first plane deports the planes are 2670 kilometers apart.
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1st plane DATA:
rate = x km/hr ; time = 1 hr ; distance = x km
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2nd plane DATA:
rate = x+56 km/hr ; time = (1/2) hrs ; distance = (1/2)(x+56) km
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Equation:
dist + dist = 2670 km
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x + (1/2)x + 2670
(3/2)x = 2670
x = (2/3)(2670) = 2*890 = 1780 km (rate of the 1st plane)
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Cheers,
Stan H.
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