Traveling with the wind, an airplane travels 210 miles im 4 hours. Against the wind, it takes six hours. Find the rate of the plane in still air and the velocity of the wind.

Answer 1

210 = 4 (v+w)
210 = 6 (v-w)

105 = 2 v + 2 w
105 = 3 v - 3 w

315 = 6 v + 6 w
210 = 6 v - 6 w
--------------------add
525 = 12 v etc