Subtract 15 from the former term of 24:16, how much should be subtracted from the latter term to keep the ratio constant
把24：16的前项减去15，要使比值不变，后项要减去多少
<gadget id="calculator">8 / 3</gadget>
<output>8/3 = around 2.666667</output>

<gadget id="calculator">16 / (8/3)</gadget>
<output>6</output>

<gadget id="calculator">16 - 6</gadget>
<output>10</output>

<result>10</result>