Given values

P_commercial = 600000 # Loan balance in yuan n_commercial = 360 # Remaining number of payments (months) r_commercial = 2.85 / 100 / 12 # Monthly interest rate for commercial loan

Monthly payment calculation using the formula

M_commercial = P_commercial * (r_commercial * (1 + r_commercial)**n_commercial) / ((1 + r_commercial)**n_commercial - 1) M_commercial