There are 38 boys and 18 girls in the big class and the middle class of the kindergarten. It is known that the ratio of the number of boys to the number of girls in the big class is 5:3, and the ratio of the number of boys to the number of girls in the middle class is 3:1. Then the boys in the middle class The number is equal to how many people.
幼儿园大班和中班共有38个男生，18个女生，已知大班中男生数与女生数的比为5：3，中班中男生数与女生数的比为3：1，那么中班的男生数等于多少人．
<gadget id="calculator">5 / 3</gadget>
<output>5/3 = around 1.666667</output>

<gadget id="calculator">(5/3) * 18</gadget>
<output>30</output>

<gadget id="calculator">38 - 30</gadget>
<output>8</output>

<gadget id="calculator">3 - (5/3)</gadget>
<output>4/3 = around 1.333333</output>

<gadget id="calculator">8 / (4/3)</gadget>
<output>6</output>

<gadget id="calculator">6 * 3</gadget>
<output>18</output>

<result>18</result>