Use a batch of paper to bind exercise books, if each book binds 50 sheets, 120 books can be bound; if 100 books are bound, how many sheets can each book be bound? (Solve with ratio)
用一批纸装订练习本，若每本装订50张，可装订120本；若要装订100本，每本可装订多少张？(用比例解)
<gadget id="calculator">50 * 120</gadget>
<output>6_000</output>

<gadget id="calculator">6_000 / 100</gadget>
<output>60</output>

<result>60</result>