Mr. Li bought 8 pens and rewarded the students. Each pen is X yuan. If you pay 100 yuan, how much should you get back?
李老师买了8支钢笔奖励给学生，每支X元，付出100元，应找回多少元．
<gadget id="calculator">100 - 8</gadget>
<output>92</output>

<result>92</result>