Parking in a car parking lot requires at least 0.5 yuan once. If you park for more than 1 hour, you will have to pay 1.5 yuan more for each additional hour. A car pays 5 yuan when it leaves the parking lot. How many hours has this car been parked?
在一个汽车停车场停车一次至少要交0.5元．如果停车超过1小时，每多停1小时，要多交1.5元．一辆汽车在离开停车场时交了5元．这辆汽车停了几小时？
<gadget id="calculator">5 - 0.5</gadget>
<output>4.5</output>

<gadget id="calculator">1.5 / 1</gadget>
<output>1.5</output>

<gadget id="calculator">4.5 / 1.5</gadget>
<output>3</output>

<gadget id="calculator">3 + 1</gadget>
<output>4</output>

<result>4</result>