Lets take a scenario with the following parameters:
NPH = 3 phase,
RDROOP = 1.9mV/A,
RSENSEA = 1.05mohm,
GMD = 600uS
If we calculate the required value of RFBA by using the formula below in the datasheet we will get the following
Now what will happen if you use a resistor 9.76kohm instead of the calculated 9.048kohm?
The answer is that these are the theoretical calculation of RFBA based on the selected droop (1.9m ohm in this case). As the calculated value is 9.048kohm which theoretically corresponds to 1.9mohm droop. If we use 9.76kohm theoretically it will correspond to droop of 2mohm. However these calculated values are starting values only and actual droop should be tuned on the practical board which also include component tolerances and track resistance.