SOLUTION: Flying against the wind, an airplane travels 3060 kilometers in 6 hours. Flying with the wind, the same plane travels 7070 kilometers in 7 hours. What is the rate of the plane in s

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Question 1164594: Flying against the wind, an airplane travels 3060 kilometers in 6 hours. Flying with the wind, the same plane travels 7070 kilometers in 7 hours. What is the rate of the plane in still air and what is the rate of the wind?
Answer by ikleyn(52863) About Me  (Show Source):
You can put this solution on YOUR website!
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Let "u" be the plane speed in still air;  "v" be the speed of the wind.


Then from the condition, effective rate with the wind is

    u + v = 7070%2F7 = 1010  km/h


Effective rate against the wind is

     u -v = 3060%2F6 = 510  km/h


Add the two equations  (1)  and  (2)  to get

    2u    = 1520;  

     u    = 1520/2 = 760.


Then from equation (1),

     v    = 1010 - 760 = 250.


ANSWER.  The plane speed in the still air is  760 km/h.  The wind speed is 250 km/h.

Solved.