There are 30 people in the music interest group, of which boys account for 2/3 of girls. How many girls are in this group?
音乐兴趣小组有30人，其中男生占女生的(2/3)．这个小组中女生有多少人？
<gadget id="calculator">2 / 3</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">1 + (2/3)</gadget>
<output>5/3 = around 1.666667</output>

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

<result>18</result>