The number of white rabbits is less than that of black rabbits (1/5), the number of white rabbits is a fraction of that of black rabbits; the number of black rabbits is a fraction of that of white rabbits; the number of black rabbits is a fraction of that of white rabbits How many; what percentage of the total number of black rabbits?
白兔的只数比黑兔少(1/5)，白兔只数是黑兔的几分之几；黑兔只数是白兔的几分之几；黑兔比白兔多几分之几；黑兔只数占总只数的几分之几？
<gadget id="calculator">1 / 1</gadget>
<output>1</output>

<gadget id="calculator">5 - 1</gadget>
<output>4</output>

<gadget id="calculator">4 + 5</gadget>
<output>9</output>

<gadget id="calculator">5 / 9</gadget>
<output>5/9 = around 0.555556</output>

<result>5/9 = around 0.555556</result>