Xiao Li went to bed at 22:00 and got up at 7:00 the next day. How many hours did she sleep?
小丽22：00睡觉，第二天7：00起床，她睡了多少个小时．
<gadget id="calculator">24 - 22</gadget>
<output>2</output>

<gadget id="calculator">2 + 7</gadget>
<output>9</output>

<result>9</result>