下表显示了一项清洁工作的收费标准。

前 2 小时	每小时 $35
此后每增加一小时	$25

Mandy 支付了 $145 的清洁费用。她支付了多少小时 of 清洁服务？

1. Calculate the cost for the first 2 hours

$\text{Cost for first 2 hours} = 2 \times \char36{}35 = \char36{}70$

2. Calculate the remaining amount paid for additional hours

$\text{Remaining amount} = \char36{}145 - \char36{}70 = \char36{}75$

3. Calculate the number of additional hours

$\text{Additional hours} = \char36{}75 \div \char36{}25 = 3 \text{ hours}$

4. Calculate the total number of hours

$\text{Total hours} = 2 + 3 = 5 \text{ hours}$