A train M leaves City A at 5 am and reaches City B at 9am. Another train N leaves City B at 7am and reaches City A at 1030am. At what time do the 2 trains cross one another?
Choose one: A) 1 hr 23 min B) 1 hr 15 min C) 1 hr 8 min D) 56 min E) 55 min
Let the distance between the cities be x   They meet after y hrs after 7am   M covers x in 4hrs   N covers x in 3 1/2 i.e 7/2 hrs   speed of M =x/4   speed of N = 2x/7   56 ministance covered by M in y+2 hrs + 56 ministance covered by N in   y hrs is x   x/4 (y+2) +2x/7(y)=x   y=14/15hr or 56 min   Answer : 56 min.
<result>D</result>
A train M leaves City A at 5 am and reaches City B at 9am. Another train N leaves City B at 7am and reaches City A at 1030am. At what time do the 2 trains cross one another?