<PRE><B>Question 1038571</B>
 two trains start simultaneously from p &amp; q which are 400 km apart.
 the speed of of the train is 5 km/hour is greater than the other .
after two hours the distance between the train is 90km find the speed of the train.
:
If the trains are 90 km apart, the sum of the distances the trains have traveled:
400 - 90 = 310 km
:
let s = the speed of the faster train
then
(s-5) = the speed of the other train
:
Write a distance equation dist = time * speed 
2s + 2(s-5) = 310
2s + 2s - 10 = 310
4s = 310 + 10
4s = 320
s = 320/4
s = 80 km/hr is the faster train
:
:
Confirm this, find actual distances each train traveled in 2 hr
2(80) = 160 km
2(75) = 150 km (5 km/hr slower)
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total dist 310 km</PRE>