Two gears, A and B, have a tooth ratio of 3:5, and they mesh with each other. When gear A makes 50 revolutions, how many revolutions does gear B make?
甲乙两个齿轮齿数比是3：5，它们互相咬合．当甲齿轮转50圈时，乙齿轮转多少圈．
<gadget id="calculator">50 / 5</gadget>
<output>10</output>

<gadget id="calculator">10 * 3</gadget>
<output>30</output>

<result>30</result>