Train A left Centerville Station, heading toward Dale City Station, at 3: 00 p.m. Train B left Dale City Station, heading toward Centerville Station, at 5: 20 p.m. on the same day. The trains rode on straight tracks that were parallel to each other. If Train A traveled at a constant speed of 30 miles per hour and Train B traveled at a constant speed of 10 miles per hour, and the distance between the Centerville Station and Dale City Station is 90 miles, when did the trains pass each other?  Choose the correct choice:
A) 4: 45 p.m.
B) 5: 00 p.m.
C) 5: 20 p.m.
D) 5: 35 p.m.
E) 7: 20 p.m.
the distance travelled by the train A in first 20 minutes will be 10.   The distance which will be remaining is 80.   Now both trains are running in opposite direction.Their speed will be added so 40.   Time at which they will meet =80/40= 
<gadget id="calculator">80/40</gadget>
<output>2</output>
2   time of train B will be 5:20 +2=7:20   Hence answer is 7: 20 p.m..Hope i am correct
<result>E</result>
Train A left Centerville Station, heading toward Dale City Station, at 3: 00 p.m. Train B left Dale City Station, heading toward Centerville Station, at 5: 20 p.m. on the same day. The trains rode on straight tracks that were parallel to each other. If Train A traveled at a constant speed of 30 miles per hour and Train B traveled at a constant speed of 10 miles per hour, and the distance between the Centerville Station and Dale City Station is 90 miles, when did the trains pass each other?