The number of A is (2/5) of the number of B, the number of A is 80, what is the number of B
甲数是乙数的(2/5)，甲数是80，乙数是多少
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">80 / (2/5)</gadget>
<output>200</output>

<result>200</result>