  We show that the values of the first three cumulants of the baryon number
distribution can be used to calculate the isothermal speed of sound and its
logarithmic derivative with respect to the baryon number density. We discuss
applications of this result to heavy-ion collision experiments and address
possible challenges, including effects due to baryon number conservation,
differences between proton and baryon cumulants, and the influence of finite
number statistics on fluctuation observables in both experiment and hadronic
transport simulations. In particular, we investigate the relation between
quantities calculated in infinite, continuous matter and observables obtained
in simulations using a finite number of particles.
