The repayable principal of each installment of the bill is equal to the total installment principal divided by the number of installments. The principal payable for each installment is credited to the cardholder's credit card account every month, and the balance is credited to the last installment. After the bill installment is successful, the cardholder only needs to repay the remaining bill amount after deducting the bill installment amount before the due repayment date. After that, the repayable principal of each installment of the bill = total installment principal ÷ number of installments.