Answer:
The speed of one plane = 257.5 miles per hour
And speed of second plane = 332.5 miles per hour
Step-by-step explanation:
We have given,
Distance between two cities = 960 miles
Two planes are flying towards each other.
Let the speed of one plane be x.
Then,
Speed of second plane = x+75 {Following this "one of the planes' speed exceeds the other by 75 mph"]
After 1.5 hours they are still 75 miles apart.
i.e Relative distance between two planes = Relative speed of plane × Time
Here
relative speed = x + (x+75) , and relative distance left to cover = 960-75.
i.e
(960 - 75) = {x+(x+75)}×1.5
885 = (2x+75)×1.5
or
or 590-75 = 2x
or 515 = 2x
or x = = 257.5
Hence the speed of one plane = x = 257.5 miles per hour
And speed of second plane = (x+75) = 257.5 + 75 = 332.5 miles per hour