## anonymous one year ago An airplane flies against the wind from A to B in 8 hours. The same airplane returns from B to A, in the same direction as the wind, in 7 hours. Find the ratio of the speed of the airplane (in still air) to the speed of the wind.

1. mathstudent55

The airplane speed in still air is v. The wind speed is w. The plane speed with the wind is v + w. The plane speed against the wind is v - w.

2. mathstudent55

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3. mathstudent55

$$\begin{cases} d = 8(v - w\\ d = 7(v + w) \end{cases}$$ $$\begin{cases} d = 8v - 8w \\ d = 7v + 7w \end{cases}$$ $$8v - 8w = 7v + 7w$$ $$v = 15w$$ $$\dfrac{v}{w} = \dfrac{15}{1}$$

4. anonymous

Thanks :)

5. mathstudent55

You're welcome.

6. anonymous

Can you help with a few more

7. mathstudent55

Yes. Pls start a new post for each new problem. I''ll look for them.

8. anonymous

Ok