Final answer:
The equation that can be used to calculate his commission (c) last month is: c = 0.745 × y.
Step-by-step explanation:
The equation that can be used to calculate his commission (c) last month is: c = 0.745 × y.
In this equation, 'c' represents the commission and 'y' represents a known value (30.00 in this case). To calculate the commission, you would multiply 0.745 by the known value (30.00).