The number of A is 40 more than the number of B. This difference is exactly (1/5) of the number of B. What is the number of B?
甲数比乙数多40，这个差恰好占乙数的(1/5)，乙数是多少．
<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">40 / (1/5)</gadget>
<output>200</output>

<result>200</result>