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 16 hours and 4 hours respectively. The ratio of their speeds is: Choose the correct choice from the following answers:
A) 2 : 4  B) 4 : 3  C) 6 : 7  D) 9 : 16  E) none of these

Rationale: "let us name the trains as a and b . then , ( a ' s speed ) : ( b ' s speed ) = â ˆ š b : â ˆ š a = â ˆ š 4 : â ˆ š 16 = 2 : 4 . answer a"
Answer: A