  Multiplicity distributions and event-by-event multiplicity fluctuations in
AuAu collisions at energies in future heavy-ion experiment at the Facility for
Anti-proton and Ion Research (FAIR) are investigated. Events corresponding to
FAIR energies are simulated in the frame work of Ultra Relativistic Quantum
Molecular Dynamics (URQMD) model. It is observed that the mean and the width of
multiplicity distributions monotonically increase with beam energy. The trend
of variations of dispersion with mean number of participating nucleons for the
centrality-bin width of 5\% are in accord with the Central Limit Theorem. The
multiplicity distributions in various centrality bins as well as for full event
samples are observed to obey Koba, Nielsen and Olesen (KNO) scaling. The trends
of variations of scaled variance with beam energy are also found to support the
KNO scaling predictions for larger collision centrality. The findings also
reveal that the statistical fluctuations in 5\% centrality-bin width appear to
be under control.
