If a number is increased by 20%, it is 4.8, so what is the number?
一个数增加二成后是4.8，那么这个数是多少．
<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 + (1/5)</gadget>
<output>6/5 = around 1.2</output>

<gadget id="calculator">4.8 / (6/5)</gadget>
<output>4</output>

<result>4</result>