Question 993954
plane's speed in calm air=x
wind speed=w
x-w=150 ;; 300 miles in 2 hours is 150 mph
For x+w, we know that 300 miles is done in 3/2 hours.  That is 200 mph.
Therefore
x-w=150
x+w=200
2x=350
x=175 mph, speed of plane in still air.
wind speed is 25 mph (headwind/tailwind)