Li Ming went to the bookstore and bought a set of "One Hundred Thousand Whys". After paying 50 yuan to the salesperson, he got 1.5 yuan back.
李明到书店买了一套《十万个为什么》，付给营业员50元后又找回了1.5元，这套书每本9.7元，请根据上述条件提出相关的数学问题并解答．
<gadget id="calculator">50 - 1.5</gadget>
<output>48.5</output>

<gadget id="calculator">48.5 / 9.7</gadget>
<output>5</output>

<result>5</result>