A siren placed at a railway platform is emitted sound of frequency 5 kHz. A passenger sitting in a moving train A records a frequency of 5.5 kHz while the train approaches the siren. During his return journey in a different train B he records a frequency of 6.0 kHz while approaching the same siren. The ratio of the velocity of train B that of train A is
1
\(\dfrac{242}{252}\)
2
\(2\)
3
\(\dfrac{5}{6}\)
4
\(\dfrac{11}{6}\)