SOLUTION: A freight train, traveling at an average rate of 30mi/hr, leaves San Francisco for Los Angeles. Five hours later, a passenger train, traveling at an average rate of 55mi/hr, leaves

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Question 757830: A freight train, traveling at an average rate of 30mi/hr, leaves San Francisco for Los Angeles. Five hours later, a passenger train, traveling at an average rate of 55mi/hr, leaves San Francisco for Los Angeles. How far are the trains from San Francisco when the passenger train passes the freight train?
Answer by josgarithmetic(39616) About Me  (Show Source):
You can put this solution on YOUR website!
Freight train is 30%2A5=150 miles from San Francisco when the passenger train just begins departing from San Francisco.

Setting time, x = 0 when the passenger train starts, distances from San Francisco are:
Freight: 150%2B30%2Ax
Passenger: 55%2Ax
Question: When are the distances for each train from San Francisco equal? HOW FAR ARE THEY FROM San Francsisco AT THAT TIME?

150%2B30x=55x
%2855-30%29x=150
25x=150
highlight%28x=6%29 hours

Pick either distance equation. The two trains are 55%2A25=highlight%281375%29 miles from San Francisco.