Multiply the former term of the ratio by (1/3), to keep the ratio unchanged, what should be the latter term.
比的前项乘(1/3)，要使比值不变，后项应该多少．
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<result>1/3 = around 0.333333</result>