The sum of the number of fruit candies in the fruit box is exactly 3 times the number of chocolates. If you take out 4 fruit candies and 2 chocolates each time, after taking several times, there are only 18 fruit candies left in the fruit box. How many chocolates are there?
果盒中水果糖的个数和正好是巧克力个数的3倍，如果每次拿出4个水果糖，2个巧克力，拿若干次后，果盒中只剩下18个水果糖．拿出的巧克力有多少个．
<gadget id="calculator">2 * 3</gadget>
<output>6</output>

<gadget id="calculator">6 - 4</gadget>
<output>2</output>

<gadget id="calculator">18 / 2</gadget>
<output>9</output>

<gadget id="calculator">2 * 9</gadget>
<output>18</output>

<result>18</result>