There are 42 students in Class 6 and 2. Girls account for 3/7 of the class. How many more boys than girls?
六2班有学生42人，女生占全班人数的(3/7)，男生比女生多多少人？
<gadget id="calculator">3 / 7</gadget>
<output>3/7 = around 0.428571</output>

<gadget id="calculator">42 * (3/7)</gadget>
<output>18</output>

<gadget id="calculator">42 - 18 - 18</gadget>
<output>6</output>

<result>6</result>