  The standard interpretation of observations such as the peak apparent
magnitude of Type Ia supernova made from one location in a lumpy Universe is
based on the idealised Friedmann-Lema\^itre Robertson-Walker spacetime. All
possible corrections to this model due to inhomogeneities are usually
neglected. Here, we use the result from the recent concise derivation of the
area distance in an inhomogeneous universe to study the monopole and Hubble
residual of the apparent magnitude of Type Ia supernovae. We find that at low
redshifts, the background FLRW spacetime model of the apparent magnitude
receives corrections due to relative velocity perturbation in the observed
redshift. We show how this velocity perturbation could contribute to a variance
in the Hubble residual and how it could impact the calibration of the absolute
magnitude of the Type Ia supernova in the Hubble flow. We also show that it
could resolve the tension in the determination of the Hubble rate from the
baryon acoustic oscillation and local measurements.
