In the ratio, the two internal terms are reciprocals of each other, one external term is 0.6, and the other external term is how much.
在比例中，两个内项互为倒数，一个外项是0.6，另一个外项是多少．
<gadget id="calculator">1 / 0.6</gadget>
<output>1.666667</output>

<result>1.666667</result>