SOLUTION: Two trains start at the same time from two stations and proceed towards each other with speed 40km/hr and 45km/hr respectively. When they meet it is found that one train has travel

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Question 883516: Two trains start at the same time from two stations and proceed towards each other with speed 40km/hr and 45km/hr respectively. When they meet it is found that one train has travelled 40km more than the other. Find the distance between the two stations.
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +d+ km = the distance that the
+40+ km/hr train travels
+d+%2B+40+ km = the distance the
+45+ km/hr train travels
---------------------------------------
Let +t+ = the time in hrs for them to meet
Equation for +40+ km/hr train:
(1) +d+=+40t+
Equation for +45+ km/hr train:
(2) +d+%2B+40+=+45t+
-------------------------
By substitution:
(2) +40t+%2B+40+=+45t+
(2) +5t+=+40+
(2) +t+=+8+
and
(1) +d+=+40t+
(1) +d+=+40%2A8+
(1) +d+=+320+
and
+d+%2B+40+=+360+
-----------------------
+d+%2B+d+%2B+40+=+320+%2B+360+
+d+%2B+d+%2B+40+=+680+
The stations are 680 km apart
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check answer:
I can think of one train standing still and
the other traveling at the sum of their speeds
for the whole +680+ km for +8+ hrs
+680+=+%28+40+%2B+45+%29%2A8+
+680+=+85%2A8+
+680+=+680+
OK