The speed of sound is the distance travelled per unit of time. In different environment, the speed is different, at sea level, In dry air at 20 °C (68 °F), the speed of sound is 343 metres per second.
c = sqrt [ γ * (p0/ ρ )]
where ρ = Density [kgm-3], P0 = Pressure [Pa], γ = Ratio of specific heats.
For example, When Ratio of specific heats, γ = 3, pressure, P0 = 4 Pa, density = 3kgm-3, Then speed of sound is 2 m/s.