The school bought 42 packs of exercise books, 20 books in each pack. Each class is divided into 84 books, how many people can be divided into classes?
学校买来42包练习本，每包20本．每班分84本，能够分给几人班？
<gadget id="calculator">20 / 84</gadget>
<output>5/21 = around 0.238095</output>

<gadget id="calculator">42 * (5/21)</gadget>
<output>10</output>

<result>10</result>