There are 12 chickens and rabbits, and 38 legs. How many rabbits are there?
鸡和兔一共有12只，腿有38条，其中兔有多少只．
<gadget id="calculator">12 * 2</gadget>
<output>24</output>

<gadget id="calculator">38 - 24</gadget>
<output>14</output>

<gadget id="calculator">4 - 2</gadget>
<output>2</output>

<gadget id="calculator">14 / 2</gadget>
<output>7</output>

<result>7</result>