In a ratio, the two outer terms are reciprocals of each other, one of the inner terms is (3/7), and the other inner term is
在一个比例中，两个外项互为倒数，其中一个内项是(3/7)，另一个内项是多少
<gadget id="calculator">3 / 7</gadget>
<output>3/7 = around 0.428571</output>

<gadget id="calculator">1 / (3/7)</gadget>
<output>7/3 = around 2.333333</output>

<result>7/3 = around 2.333333</result>