Question 897178
if the 2 planes are coming to each other... The sum of their velocities are equal to the the velocity that both of them getting closer.

Lets think ones velocity is x. Others should be (x+140)

Their sum should be equal to the relative velocity from earth.

(2x +140) mph

So we can write it with the distance and time.

{{{1.5 = 1530/(2x+140)}}}

{{{3x + 210 = 1530}}}

{{{3x = 1320}}}

{{{x = 440}}} mph

So it's the first planes Velocity and the others Ones is 580 mph