SOLUTION: Two planes, which are 1680 miles apart, fly toward each other. Their speeds differ by 40 mph. If they pass each other in 2 hours, what is the speed of each?

Algebra.Com
Question 1017269: Two planes, which are 1680 miles apart, fly toward each other. Their speeds differ by 40 mph. If they pass each other in 2 hours, what is the speed of each?
Answer by ikleyn(52887)   (Show Source): You can put this solution on YOUR website!
.
Two planes, which are 1680 miles apart, fly toward each other. Their speeds differ by 40 mph.
If they pass each other in 2 hours, what is the speed of each?
--------------------------------------------------------------- 

Let x be the speed of the slower plane, in mph.
The the speed of the other plane is x +40 mph.

The distance between two planes decreases at the rate x + (x+40) = 2x + 40 mph.

You have this equation

 = 2.

Solve it. For it, multiply both sides by (2x + 40). You will get

1680 = 2*(2x + 40),   or

1680 = 4x + 80,   or

4x = 1600.

Hence, x =  = 400 mph. It is the speed of the slower airplane.
The speed of the faster is 400 + 40 = 440 mph.


RELATED QUESTIONS

Two planes, which are 1180 miles apart, fly toward each other. Their speeds differ by 40... (answered by richwmiller,lwsshak3)
Two planes, which are 2760 miles apart, fly toward each other. Their speeds differ by 40... (answered by advanced_Learner)
Two planes, which are 1570 miles apart, fly toward each other. Their speeds differ... (answered by Alan3354)
Two planes, 2000 miles apart, fly toward each other. Their speeds differ by 35 mph. If... (answered by ewatrrr)
two planes which are 2745 miles apart fly toward each other. Their speeds differ by 65... (answered by josmiceli)
Two planes which are 2160 miles apart fly toward each other. Their speeds differ by 70... (answered by mananth)
Two planes, which are 4425 miles apart, fly toward each other. their speeds differ by 35... (answered by nerdybill)
Question : two planes which are 2385 miles apart fly toward each other. Their speeds... (answered by mananth)
Two planes which are 2475 miles apart fly toward each other. Their speeds differ by 75... (answered by radh,graphmatics)