Answer : The speed of both planes is 61.25 mph and 18.75 mph respectively.
Explanation:
Let the speed of first plane be x mph
Let the speed of second plane be y mph
Since we have given that difference of speeds is 80 mph
i.e. x - y= 80 ( 1)
Distance between two planes = 3400 miles
As they are flying towards each other i.e. they are in the opposite direction.
So, Relative speed will be the sum of their speeds i.e.
Relative speed = x + y
And we know speed =
Speed=
⇒ Speed = 42.5 mph
Hence, Relative speed becomes 42.5 mph
⇒ x+y=42.5 ( 2)
Now, by using the elimination method of solving the system of equation, we have ,
x= 61.25 mph
and y = 18.75 mph