Two trains, one from Howrah to Patna and the other from Patna to Howrah, start simultaneously. After they meet, the trains reach their destinations after 4 hours and 10 hours respectively. The ratio of their speeds is Select the correct option:
A) 4 : 9  B) 4 : 3  C) 4 : 12  D) 4 : 8  E) 5 : 2
Let us name the trains as A and B. Then, (A's speed) : (B's speed) = b : a = 10 : 4 = 5 : 2.
Answer: 5 : 2
<result>E</result>
Two trains, one from Howrah to Patna and the other from Patna to Howrah, start simultaneously. After they meet, the trains reach their destinations after 4 hours and 10 hours respectively. The ratio of their speeds is