The 4200 km trip from New York to San Francisco take 6 h flying against the wind but only 5 h returning. Find the speed of the plane in still air and the speed of the wind.

Answer 1

4200/(p-w) = 6
4200/(p+w) = 5

p = 770
w = 70

check:
4200/840 = 5
4200/700 = 6