The former term of the ratio is enlarged by 5 times, and the latter term remains unchanged. How many times does the ratio expand
比的前项扩大5倍，后项不变．比值扩大多少倍
<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 / (1/5)</gadget>
<output>5</output>

<result>5</result>