SOLUTION: Erica Suco can fly her plane 200 mi against the wind and in the same time it takes her to fly 300 mi with the wind. The wind blows at 30 mph. Find the speed of her plane in still a
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-> SOLUTION: Erica Suco can fly her plane 200 mi against the wind and in the same time it takes her to fly 300 mi with the wind. The wind blows at 30 mph. Find the speed of her plane in still a
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Question 269101: Erica Suco can fly her plane 200 mi against the wind and in the same time it takes her to fly 300 mi with the wind. The wind blows at 30 mph. Find the speed of her plane in still air? Answer by checkley77(12844) (Show Source):
You can put this solution on YOUR website! D=RT OR T=D/R
T=200/(R-30)
T=300/(R+30)
THE 2 TIMES ARE EQUAL THUS THE EQUATIONS ARE EQUAL
200/(R-30)=300/(R+30) CROSS MULTIPLY
300(R-30)=200(R+30)
300R-9000=200R+6000
300R-200R=6000+9000
100R=15000
R=15000/100
R=150 MPH IS THE SPEED OF THE PLANE IN STILL AIR.
PROOF:
200/(150-30)=300/(15+30)
200/120=300/180
5/3=5/3
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