If you do it in monthly terms your interest rate is r/12 because there are twelve months in a year.

如果是每月还款那么月利率是r/12,因为一年有12个月

耶鲁公开课 - 金融市场课程节选

If they quote the rate on the mortgage, call that r Traditionally you would be paying monthly.

如果给定贷款利率,记为r,通常你是每月还款

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