Divide the former term of the ratio by (1/5), to keep the ratio constant, what should be the latter term of the ratio.
比的前项除以(1/5)，要使比值不变，比的后项应该多少．
<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<result>1/5 = around 0.2</result>