Parking in a parking lot costs at least 8 yuan once. If you park for more than 3 hours, you will have to pay an additional 2.5 yuan for each additional hour of parking. The car was parked for 9 hours, how much is a car paid when it leaves?
在一个停车场停车一次至少要交费8元．如果停车超过3小时，每多停1小时车要多交2.5元．这辆车停了9个小时，一辆汽车在离开时交了多少元？
<gadget id="calculator">9 - 3</gadget>
<output>6</output>

<gadget id="calculator">2.5 * 6</gadget>
<output>15</output>

<gadget id="calculator">15 + 8</gadget>
<output>23</output>

<result>23</result>