Question 668193:  Can you help me with this problem: A Fly By Night Airlines plane is traveling at 600 miles per hour with all three engines running. After it has flown for x hours, the pilot turns off the middle engine to conserve fuel. The speed after engine shutdown is 500 miles per hour. If the total flight time is 6 hours, how long into the flight is the engine shut down for a 3400 mile cross country flight? 
 Answer by stanbon(75887)      (Show Source): 
You can  put this solution on YOUR website! Can you help me with this problem:  
A Fly By Night Airlines plane is traveling at 600 miles per hour with all three engines running.After it has flown for x hours, the pilot turns off the middle engine to conserve fuel. 
distance traveled = 600x miles 
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The speed after engine shutdown is 500 miles per hour.  
If the total flight time is 6 hours 
distance traveled = 500(6-x) miles 
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, how long into the flight is the engine shut down for a 3400 mile cross country flight? 
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Equation: 
600x + 500(6-x) = 3400 miles 
600x + 3000 - 500x = 3400 
100x = 400 
x = 4 hrs (time the plane flew on 3 engines) 
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6-x = 2 hrs (time the plane flew on 2 engines) 
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Cheers, 
Stan H. 
 
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