Xiaohong read 24 pages in 3 days. At this speed, the book is 72 pages. How many days can she finish reading?
小红3天读了24页数，照这样的速度，全书72页，几天可以读完？
<gadget id="calculator">24 / 3</gadget>
<output>8</output>

<gadget id="calculator">72 / 8</gadget>
<output>9</output>

<result>9</result>