Question 227725
An airplane flew with the wind for 5 hours. The return trip against the wind took 6 hours.  If the wind was blowing at 25mph.  What was the rate of the plane in still the air?


Step 1.  distance= speed * time


Step 2.  Let x+25 be the airplane speed with the wind.


Step 3.  Let x-25 be the airplane speed against the wind.


Step 4.  Let 5(x+25) be the distance traveled with the wind after 5 hours.


Step 5.  Let 6(x-25) be the distance traveled again the wind after 6 hours.


Step 6.  Equate Steps 4 and 5 since the distances are the same.


{{{5(x+25)=6(x-25)}}}


{{{5x+125=6x-150}}}


Add 150-5x to both sides of the equation


{{{5x+125+150-5x=6x-5x}}}


{{{275=x}}}


Check if distances are equal:  (275+25)5=(275-25)6 which is a true statement.


Step 7.  ANSWER:  The speed of the plane is 275 miles per hour.


I hope the above steps were helpful.


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And good luck in your studies!


Respectfully,
Dr J

http://www.FreedomUniversity.TV