Xiaoyang went to bed at 9:30 in the evening and got up at 6:00 the next morning. How many hours did he sleep in total?
小阳晚上9：30睡觉，第二天早上6时起床，他一共睡了多少小时．
<gadget id="calculator">12 - 9.5</gadget>
<output>2.5</output>

<gadget id="calculator">2.5 + 6</gadget>
<output>8.5</output>

<result>8.5</result>