ratio of bad debts to credit sales

例句：

1. 1. The company's profit margin is 20% of its sales, which is a good ratio.
   该公司的利润边际是其销售额的20%，这是一个良好的比例。
2. 2. The teacher explained the problem in the ratio of parts to parts.
   老师以部分对部分的比例解释了这个问题。
3. 3. The ratio of sugar to water was 1:1.
   糖和水的比例是1:1。