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 overtakes the freight train?  Choose the correct choice from the following answers.
A) 6hours
B) 5hours
C) 9ours
D) 2hours
E) 4 hours
Read the problem. It is a time, rate, and distance problem. (Use D=r*t)   The question asks, “how long?” (which means time) for the passenger train.   Let t=the time it takes the passenger train to overtake the freight train   t+2=the number of hours the freight train had traveled when overtaken.   Draw a sketch and make a table.   Time Rate Distance   Freight t+2- 40 mph- 40(t+2)   Passengert- 60 mph-60t   Equation: When the passenger train overtakes the freight train, they have both traveled   the same distance. Write each of their distances in terms of ratetime (as seen in the   table above), then set them equal to each other to create an equation. Then solve the   equation.   40(t+2)=60t   40t+80=60t   80=20t   t=4   The answer: It takes the passenger train 4 hours to overtake the freight train.   Check by substituting 4 into the original equation.   40(4+2)=60(4)   40(6)=240   240=240   true   Thus, 4 hours is the correct answer.   correct answer 4 hours
<result>E</result>
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 overtakes the freight train?