In a ratio, the two outer terms are reciprocals of each other, one of the inner terms is 20, and the other inner term is (how much)
在一个比例中，两个外项互为倒数，其中一个内项是20，另一个内项是(多少)
<gadget id="calculator">1 / 20</gadget>
<output>1/20 = around 0.05</output>

<result>1/20 = around 0.05</result>