Question 351312
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Your difficulties with story problems may well be related to your fundamental inability to follow written instructions.  When you go to the page to post your questions, the instructions clearly state: "One question per post"


Let *[tex \Large r] represent the speed of the plane in still air.  Then *[tex \Large r\ +\ 20] must be the ground speed when the plane is traveling with the wind and *[tex \Large r\ -\ 20] must be the ground speed when the plane is traveling against the wind.  Let *[tex \Large t] represent the flight time in either direction.


Since we know that *[tex \Large d\ =\ rt], we can also say:  *[tex \Large t\ =\ \frac{d}{r}]


For the with the wind trip:


*[tex \LARGE\ \ \ \ \ \ \ \ \ \ t\ =\ \frac{500}{r\ +\ 20}]


For the against the wind trip:


*[tex \LARGE\ \ \ \ \ \ \ \ \ \ t\ =\ \frac{340}{r\ -\ 20}]


Since the time was the same for both directions, we can say:



*[tex \LARGE\ \ \ \ \ \ \ \ \ \ \frac{500}{r\ +\ 20}\ =\ \frac{340}{r\ -\ 20}]


Solve for *[tex \Large r].


John
*[tex \LARGE e^{i\pi} + 1 = 0]
My calculator said it, I believe it, that settles it
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