SOLUTION: A plane flies 900 miles, with a tail wind, in 3 hours. It takes the same plane 5 hours to fly the 900 miles when flying against the wind. Which is the plane's speed in still air. (
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Question 23795: A plane flies 900 miles, with a tail wind, in 3 hours. It takes the same plane 5 hours to fly the 900 miles when flying against the wind. Which is the plane's speed in still air. (a) 240 mph (b) 270 mph (c) 300 mph (d) 60 mph
Now I know this question is in relation to Rate times Time = Distance. But Im confused on where to put the numbers to solve the problem. Thanks so much. Answer by Paul(988) (Show Source):
You can put this solution on YOUR website! Let the speed of the wind be y
Let the speed of the plane be x
3(x+y)=900 ------------------> 3x+3y=900 (Equation 1)
5(x-y)=900 ------------------> 5x-5y=900 (Equation 2)
Multiply equation 1 by 5 and equation 2 by 3
15x+15y=4500 ----->Add
15x-15y=2700 ----->Add
30x=7200
x=240
Hence, the speed of the plane in still air is 240 mph.
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