Question

against the wind a small plane flew 280 miles in 1 hour and 10 minutes. the return trip took only 50 minutes. What was the speed of the wind? what was the speed of the plane in still air?

Answer 1

1)  1hour 10minutes = $\frac{7}{6}$ hours,
              50 minutes = $\frac{5}{6}$  hours

2) speed of plane against the wind = $\frac{280miles}{ \frac{7}{6} } = \frac{280*6}{7}=240miles /hours$

3) speed of plane on the the wind =$\frac{280miles}{ \frac{5}{6} } = \frac{280miles*6}{5}=336miles/hours$

4) (336-240):2=48miles/hours  - speed of wind
5)336-48=288miles/hours - plane's speed in still air

Answer: speed of wind is 48 miles/hours, speed of  plane in still air is 288 miles/hours