The number A is 20, the number B is (1/5) of the number A, what is the number B?
甲数是20，乙数是甲数的(1/5)，乙数是多少．
<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

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

<result>4</result>