How does sound travel through a medium?
This totally depends on the medium in question.
This has no definite answer, since it depends on the medium. Check up Wikipedia on "Speed of sound". Some facts taken from there:
Some numbers taken from Wikipedia:
In air: sound travels at 343 m/s
In water: it travels at 1,484 m/s (4.3 times as fast as in air)
In rion; 5,120 m/s (about 15 times as fast as in air).
In an exceptionally stiff material such as diamond, sound travels at 12,000 metres per second