Add 20 to the former term of 5:11, to keep the ratio unchanged, how much should be added to the latter term of the ratio.
把5：11的前项增加20，要使比值不变，比的后项应加上多少．
<gadget id="calculator">11 * 5</gadget>
<output>55</output>

<gadget id="calculator">55 - 11</gadget>
<output>44</output>

<result>44</result>