flying with the wind a plane went 408 mph flying into the sa

flying with the wind a plane went 408 mph. flying into the same wind the plane only went 330mph. find the speed of the wind and the speed of the plane in still air.

Solution

(408-330)/2=78/2=39 mph. was the wind speed.
408-39=369 mph. for the plane.
330+39=369 ditto.