Add 8 to the former term of (8/15), if the ratio is to remain unchanged, how much should the latter term be multiplied by.
(8/15)的前项加上8，如果要使比值不变，后项应该乘上多少．
<gadget id="calculator">8 + 8</gadget>
<output>16</output>

<gadget id="calculator">16 / 8</gadget>
<output>2</output>

<result>2</result>