The fourth-grade students rent boats for the spring outing. If each boat takes 10 people, there will be 2 more seats; Q: How much does it cost to rent a boat?
四年级同学春游时租船游湖，若每只船乘10人，则还多2个座位；若每只船多坐2人，可少租一条船，这时每人可节省5角钱．问：租一只船需多少元钱．
<gadget id="calculator">2 - 2</gadget>
<output>0</output>

<gadget id="calculator">10 + 0</gadget>
<output>10</output>

<gadget id="calculator">2 - 10</gadget>
<output>-8</output>

<gadget id="calculator">10 + (-8)</gadget>
<output>2</output>

<gadget id="calculator">10 / 2</gadget>
<output>5</output>

<gadget id="calculator">5 * 10</gadget>
<output>50</output>

<gadget id="calculator">50 - 2</gadget>
<output>48</output>

<gadget id="calculator">48 * 0.5</gadget>
<output>24</output>

<result>24</result>