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 64 hours and 25 hours respectively. The ratio of their speeds is?	Choose the correct choice:
A) 4 : 9
B) 4 : 3
C) 4 : 5
D) 5 : 8
E) 4 : 2

Rationale: "let us name the trains a and b . then , ( a ' s speed ) : ( b ' s speed ) = √ b : √ a = √ 25 : √ 64 = 5 : 8 answer : d"
Answer: D