SOLUTION: A local train and express train are on two adjacent tracks. Both starting at the same time they go from A to B. The express trail travels 120kilometers. It averages 20km per hour f

Algebra ->  Equations -> SOLUTION: A local train and express train are on two adjacent tracks. Both starting at the same time they go from A to B. The express trail travels 120kilometers. It averages 20km per hour f      Log On


   



Question 807615: A local train and express train are on two adjacent tracks. Both starting at the same time they go from A to B. The express trail travels 120kilometers. It averages 20km per hour faster than the local train. If the local train still has 80 kilometers to go when the express train arrives at B, what is the average speed of the express train?
Express train has traveled 120km (distance)....its rate is x+20 (rate)...the time is 120/x+20 (?)
local train has traveled 120-80km...40 (distance)...rate is x....time is 40/x (?)
please help!
it is asking for the speed of the express train

Answer by richwmiller(17219) About Me  (Show Source):
You can put this solution on YOUR website!
(x+20)*t=120, x*t=40
t = 4, x = 10
x+20=30 express train