  We give formulas for individual black hole masses in a merger, by using
Newtonian physics, in terms of the three measured quantities in the detector:
the initial wave frequency $f_1$, the maximum detected frequency (chirp
frequency) $f_2$, and the time elapse $\tau$ between these two frequencies.
Newtonian gravity provides an excellent pedagogical tool to understand the
basic features of gravitational wave observations, but it must be augmented
with the assumption of gravitational radiation from General Relativity for
accelerating masses as there is no gravitational wave in Newtonian gravity. The
simplest approach would be to consider a binary system of two non-spinning
masses (two black holes) circling their common center of mass. All the
computations can be done within Newtonian physics, but the General Relativistic
formula for the power carried by gravitational waves is required in this
scheme. It turns out there is a subtle point: for the consistency of this
simple, yet pedagogical computation, taking the lowest order power formula from
General Relativity leads to complex individual masses. Here we remedy this
problem and {suggest} a way to write down an average power formula coming from
perturbative General Relativity.
