The breeding group raises 3 white rabbits and 4 black rabbits. There are 5 gray rabbits, what is the total number of gray rabbits
饲养小组养白兔3只，黑兔4只．灰兔5只，灰兔只数是总数的多少
<gadget id="calculator">3 + 4 + 5</gadget>
<output>12</output>

<gadget id="calculator">5 / 12</gadget>
<output>5/12 = around 0.416667</output>

<result>5/12 = around 0.416667</result>