The charging standard of a certain parking lot is: (1, 2.50 yuan for less than 1 hour, 2.50 yuan for every 0.5 hours exceeding 1 hour, Uncle Li paid 12.5 yuan, how many hours does he park in this parking lot?
某停车场的收费标准是：(1,1小时以内收费2.50元，2超过1小时，每0.5小时，收费2.50元，李叔叔交了12.5元，他在这个停车场停车几小时？
<gadget id="calculator">12.5 - 2.5</gadget>
<output>10</output>

<gadget id="calculator">10 / 2.5</gadget>
<output>4</output>

<gadget id="calculator">4 * 0.5</gadget>
<output>2</output>

<gadget id="calculator">2 + 1</gadget>
<output>3</output>

<result>3</result>