The number of A is 20% less than the number of B, the number of A is 36, what is the number of B.
甲数比乙数少20%，甲数是36，乙数是多少．
<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 - (1/5)</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">36 / (4/5)</gadget>
<output>45</output>

<result>45</result>