SOLUTION: A six passenger plane cruises at 180mph in calm air. If the plane flies 7 miles with the wind in the same amount of time as it flies 5 miles against the wind then what is the speed

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Question 260976: A six passenger plane cruises at 180mph in calm air. If the plane flies 7 miles with the wind in the same amount of time as it flies 5 miles against the wind then what is the speed?
T = D/R

Answer by checkley77(12844) About Me  (Show Source):
You can put this solution on YOUR website!
T=D/R
T=7/(180+W)
T=5/(180-W)
SET THE TIME EQUATIONS EQUAL.
7/(180+W)=5/(180-W)
5(180+W)=7(180-W)
900+5W=1,260-7W
5W+7W=1,260-900
12W=360
W=360/12
W=30 MPH. FOR THE WIND SPEED.
PROOF:
7/(180+30)=5/(180-30)
7/210=5/150
1/30=1/30