question?

I

iamtoostinky

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An aircraft with a constant speed in still air travels 4400 km with a constant tailwind in 4 hours. With the same wind now against the aircraft, it takes 5 hours to make the return trip. What was the speed of the wind, in km/hr?

Would the correct answer be 900
 
1) Is that reasonable? 900 kmh wind! Wow!!
2) Where did your units go? It's kph, isn't it?
3) Nope. How did you set it up?
 
Please reply showing your steps, if you aren't sure of your answer.

Thank you.

Eliz.
 
iamtoostinky said:
An aircraft with a constant speed in still air travels 4400 km with a constant tailwind in 4 hours. With the same wind now against the aircraft, it takes 5 hours to make the return trip. What was the speed of the wind, in km/hr?
Would the correct answer be 900
Click to expand...
Were you too tired to do something like:

a = aircraft speed, w = wind speed:

......4400km @ (a+w) kph......: 4 hours

......4400km @ (a-w) kph.......: 5 hours

Now use formula speed = distance / time
 
Denis said:
a = aircraft speed, w = wind speed:

. . . . .4400km @ (a+w) kph......: 4 hours

. . . . .4400km @ (a-w) kph.......: 5 hours

Now use formula speed = distance / time
Click to expand...
Alternate start-up: Denis has given you a very clear set-up. Now use "d = rt" to read off two equations. Solve the resulting system. A good first step would be to divide off the "4400", which will give you Denis' suggested formulation.

:D

Eliz.
 
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