Distribute a box of candies to A, B, C, and D according to the ratio of 3:2:4:1. If B gets 12, how many candies will A get?
把一盒糖按3：2：4：1分给甲、乙、丙、丁四个孩子，若乙得12颗，甲得多少颗．
<gadget id="calculator">3 + 2 + 4 + 1</gadget>
<output>10</output>

<gadget id="calculator">2 / 10</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">12 / (1/5)</gadget>
<output>60</output>

<gadget id="calculator">3 / 10</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">60 * (3/10)</gadget>
<output>18</output>

<result>18</result>