In a ratio, the product of the two outer terms is 1, one of the inner terms is 0.2, and what is the other inner term.
一比例中，两外项的乘积为1，其中一个内项为0.2，另一个内项为多少．
<gadget id="calculator">1 / 0.2</gadget>
<output>5</output>

<result>5</result>