<PRE><B>Question 203510</B>
An express train and a local train both leave Gray’s Lake at 12:00 noon and head
 for Chicago 60 miles away. The express travels twice as fast as the local and
 arrives 2 hours ahead of it. Find the speed of each train.
:
Let s = speed of the freight
then
2s = speed of the express
:
Write a time equation: Time = {{{dist/speed}}}
Freight time = Express time + 2 hrs
{{{60/s}}} = {{{60/(2s)}}} + 2
Multiply equation by 2s, results:
2(60) = 60 + 2(2s)
120 = 60 + 4s
120 - 60 = 4s
60 = 4s
s = {{{60/4}}}
s = 15 mph is the freight, 
then
2(15) = 30 mph is express
;
:
Check solution by finding the time of each train
60/15 = 4 hr
60/30 = 2 hr
------------
differ = 2 hrs
</PRE>