The total number of credit card installments is 5000 yuan, and the number of installments is 12. Suppose the annual interest rate is the bank's standard interest rate (such as 18%), and the monthly interest rate r= annual interest rate/(12×100%) = 0.015. Substitute the parameters in the formula m = p× [r/(1-(1+r) (-n)] for calculation: m = 5000× [0.015/(1-(65430)