Expand the numerator of a fraction to 5 times the original, and reduce the denominator to the original (1/4); the value of this fraction is as much.
把一个分数的分子扩大到原来的5倍，同时分母缩小到原来的(1/4)；这个分数值就多少．
<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">5 / (1/4)</gadget>
<output>20</output>

<result>20</result>