Use a batch of paper to bind exercise books of the same size. If each book has 30 pages, 120 books can be bound. Now this batch of paper needs to bind 100 books. How many pages should each book be bound?
用一批纸装订同样大小的练习本，如果每本30页，可以装订120本，现在这批纸需要装订100本，每本应该装订多少页？
<gadget id="calculator">120 * 30</gadget>
<output>3_600</output>

<gadget id="calculator">3_600 / 100</gadget>
<output>36</output>

<result>36</result>