The school dance team recruits 20 students, 40% of whom are boys, and how many more girls are there than boys.
学校舞蹈队招收学生20人，其中男生人数占40%，女生人数比男生人数多多少人．
<gadget id="calculator">40 / 100</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">20 * (2/5)</gadget>
<output>8</output>

<gadget id="calculator">20 - 8</gadget>
<output>12</output>

<gadget id="calculator">12 - 8</gadget>
<output>4</output>

<result>4</result>