Two stations A and B are 110 km apart on a straight line. One train starts from A at 7 a.m. and travels towards B at 20 kmph. Another train starts from B at 8 a.m. and travels towards A at speed of 25 kmph. At what time will they meet?
Choose the correct answer.
A) 9 a.m.
B) 10 a.m.
C) 10.30 a.m.
D) 11 a.m.
E) None
Sol.   Suppose they meet x hours after 7 a.m.   Distance covered by A in x hours = 20 x km.   Distance covered by B in (x-1) hours = 25(x-1) km.   ∴ 20x + 25(x-1) = 110   ⇔ 45x = 135   ⇔ x = 3.   So, they meet at 10 a.m.   Answer 10 a.m.
<result>B</result>
Two stations A and B are 110 km apart on a straight line. One train starts from A at 7 a.m. and travels towards B at 20 kmph. Another train starts from B at 8 a.m. and travels towards A at speed of 25 kmph. At what time will they meet?