Two trains, traveling towards each other, left from two stations that are 900 miles apart, at 4 pm. If the rate of the first train is 72 mph and the rate of the second train is 78 mph, at whatt time will they pass each other?  Select the correct option
A) 2	B) 4	C) 6	D) 8	E) 10
After t hours, the two trains will have traveled distances D1 and D2 (in miles) given by   D1 = 72 t and D2 = 78 t   After t hours total distance D traveled by the two trains is given by   D = D1 + D2 = 72 t + 78 t = 150 t   When distance D is equal to 900 miles, the two trains pass each other.   150 t = 900   t = 6 hours.   Answer:6
<result>C</result>
Two trains, traveling towards each other, left from two stations that are 900 miles apart, at 4 pm. If the rate of the first train is 72 mph and the rate of the second train is 78 mph, at whatt time will they pass each other?