A plane flies 4 hr west with a 60-mph tailwind. Returning against the wind takes 5 hrs. Find the speed of the plane with no wind.

Answer 1

So,

V_plane + V_wind = 60 mph(1)

and

4 hr * 60 mph = 5 * (V_plane - V_wind)

V_plane - V_wind = 48 mph

V_wind = V_plane - 48(2)

if we put (2) in (1)

V_plane + V_plane - 48 = 60

2V_plane = 108

V_plane = 54 mph