There are two trains traveling towards each other. The freight train is going 15 mph and the passenger train is going 85 mph. Their total speed, relative to each other, is 15 mph + 85 mph = 100 mph.

Use the formula Distance = Rate x Time to solve the problem. The distance is 200 miles and the rate is 100 mph. Let t be the time the two trains travel.

Now we have 200 miles = (100 mph)t.

So t = 200 miles / 100 mph. t=2 hours.

The trains meet at 8:00 pm.

Using the same formula (Distance = Rate X Time) we can now determine how far each train traveled.

Freight train. d = (15 mph)(2 hours). d=30 miles.

Passenger train. d = (85 mph)(2 hours). d=170 miles.

The trains meet at Greenville, which is 30 miles from Unionville and 170 miles from Stonesboro.

 

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