There are 108 students on the playground exercising, of which girls accounted for (2/9), how many girls came later, so that the ratio of the number of girls to the number of boys was 3:7, how many girls came later?
操场上有108名同学在锻炼身体，其中女生占(2/9)，后来又来了几名女生，使女生人数和男生人数的比是3：7，后来来了几名女生？
<gadget id="calculator">2 / 9</gadget>
<output>2/9 = around 0.222222</output>

<gadget id="calculator">1 - (2/9)</gadget>
<output>7/9 = around 0.777778</output>

<gadget id="calculator">3 + 7</gadget>
<output>10</output>

<gadget id="calculator">7 / 10</gadget>
<output>7/10 = around 0.7</output>

<gadget id="calculator">(7/9) / (7/10)</gadget>
<output>10/9 = around 1.111111</output>

<gadget id="calculator">108 * (10/9)</gadget>
<output>120</output>

<gadget id="calculator">120 - 108</gadget>
<output>12</output>

<result>12</result>