Two planes left an airport at noon. One flew east in a certain speed and the other flew west at twice the speed. The planes were 2700 mi. apart in 3 hrs. How fast was each plane flying?

Question

anonymous · Answer

East 300 
West 600

anonymous · Answer

Work it out to check it

kropot72 · Answer

Let the speed of the plane flying east = s
Then the speed of the plane flying west = 2s
The two planes are flying in opposite directions. Therefore the separation speed is given by s + 2s = 3s. When the planes fly for 3 hours at the separation speed of 3s the separation distance is 2700 miles. The following equation can be written:
$$3s \times3=2700$$
which simplifies to:
$$9s=2700\ .........(1)$$
If you divide both sides of equation (1) by 9, you will have the value of s (the speed of the plane flying east). Then you can multiply that value by 2 to find the speed of the plane flying west.

anonymous · Answer

east flying speed is 900 kmph
west is at 1800 kmph