Question

A freight train starts from Los Angeles and heads for Chicago at 40 mph. Two hours later, a passenger train leaves the same station for Chicago traveling 60 mph. How long before the passenger train over takes the freight train?

Answer 1

I'm going to assume that they are on parallel tracks, and not the same track.

60x=40(x+2)

60x=40x+80

20x=80

x=4

You can check the work I've provided by filling in the answer for x into the initial question.

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