  Fast Radio Bursts (FRBs) are short timescale (<<1 s) astrophysical radio
signals, presumed to be a signature of cataclysmic events of extragalactic
origin. The discovery of six high-redshift events at ~1400 MHz from the Parkes
radio telescope suggests that FRBs may occur at a high rate across the sky. The
Murchison Widefield Array (MWA) operates at low radio frequencies (80-300 MHz)
and is expected to detect FRBs due to its large collecting area (~2500 m^2) and
wide field-of-view (FOV, ~1000 square degrees at nu=200 MHz). We compute the
expected number of FRB detections for the MWA assuming a source population
consistent with the reported detections. Our formalism properly accounts for
the frequency-dependence of the antenna primary beam, the MWA system
temperature, and unknown spectral index of the source population, for three
modes of FRB detection: coherent; incoherent; and fast imaging. We find that
the MWA's sensitivity and large FOV combine to provide the expectation of
multiple detectable events per week in all modes, potentially making it an
excellent high time resolution science instrument. Deviations of the expected
number of detections from actual results will provide a strong constraint on
the assumptions made for the underlying source population and intervening
plasma distribution.
