SOLUTION: An airplane flew for 3 hours with a tail wind of 40 km/hr. The Return flight against the same wind took 4 hours. Find The Speed of the airplane in still air.
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-> SOLUTION: An airplane flew for 3 hours with a tail wind of 40 km/hr. The Return flight against the same wind took 4 hours. Find The Speed of the airplane in still air.
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Question 147408: An airplane flew for 3 hours with a tail wind of 40 km/hr. The Return flight against the same wind took 4 hours. Find The Speed of the airplane in still air. Found 2 solutions by checkley77, ankor@dixie-net.com:Answer by checkley77(12844) (Show Source):
You can put this solution on YOUR website! D=RT
SEEING AS THE DISTANCES ARE THE SAME WE HAVE:
(R+40)3=(R-40)4
3R+120=4R-160
3R-4R=-160-120
-R=-280
R=280 KM/HR THE PLANES SPEED IN STILL AIR.
You can put this solution on YOUR website! An airplane flew for 3 hours with a tail wind of 40 km/hr. The Return flight against the same wind took 4 hours. Find The Speed of the airplane in still air.
:
Let s = speed of plane in still air
then
(s+40) = ground speed with the wind
and
(x-40) = ground speed against the wind
:
the distance both ways are assumed equal, write a distance equation:
Dist = time * speed
:
4(s-40) = 3(s+40)
:
4s - 160 = 3s + 120
;
4s - 3s = 120 + 160
:
s = 280 mph in still air
:
:
Check solution by confirming that the distances are equal
4(280-40) = 960
3(280+40) = 960
:
This is a way all these type problems can be done. Learn this and you got it!
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