下表显示了某购物中心对驾驶员收取的停车费。

	上午7点至下午6点	下午6点之后
第一小时	$2.20	每次 $2.50
此后每30分钟或不足30分钟	$1.50

林先生从下午4点到晚上7点停放他的汽车。他一共支付了多少停车费？

1. Determine the parking duration and cost for the period before 6 p.m.

From 4 p.m. to 6 p.m. is 2 hours.
Cost for the 1st hour = $\char36{}2.20$
Remaining time = 1 hour = 2 blocks of 30 minutes.
Cost for subsequent 30 minutes = $2 \times \char36{}1.50 = \char36{}3.00$
Total cost before 6 p.m. = $\char36{}2.20 + \char36{}3.00 = \char36{}5.20$

2. Determine the parking cost for the period after 6 p.m.

From 6 p.m. to 7 p.m. falls under the 'After 6 pm' rate.
Cost = $\char36{}2.50$ per entry.

3. Calculate the total parking charges.

Total charges = $\char36{}5.20 + \char36{}2.50 = \char36{}7.70$