Xiao Liang goes to school at 8:00 every morning (noon school board and lodging), and leaves school at 5:00 pm. How many hours does he spend in school a day?
小亮每天早上8时到校上课(中午在校食宿)，下午5时放学，他一天在校时间是多少小时．
<gadget id="calculator">17 - 8</gadget>
<output>9</output>

<result>9</result>