Answer:
speed of the plane = 190 mph
Step-by-step explanation:
Let x = speed of the plane, then speed of the car = x - 150
time = 200/(x - 150) = 950/x
Divide by 50 on both sides, get
4/(x - 150) = 19/x
Cross multiply:
4x = 19(x - 150)
4x = 19x - 19*150
15x = 19*150
x = 19*150/15 = 190