The number of girls in the school's track and field team originally accounted for (1/3) of the total number of track and field teams. Later, 6 girls were selected to participate in the track and field team, so that girls accounted for the total number of current track and field teams (4/9). How many girls are there?
学校田径小组原有女生的人数占田径总人数的(1/3)，后来又选出6名女生参加田径组，这样女生就占现在田径组总人数的(4/9)，现在田径组有女生多少人？
<gadget id="calculator">9 - 4</gadget>
<output>5</output>

<gadget id="calculator">4 / 5</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">3 - 1</gadget>
<output>2</output>

<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">(4/5) - (1/2)</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">6 / (3/10)</gadget>
<output>20</output>

<gadget id="calculator">20 * (4/5)</gadget>
<output>16</output>

<result>16</result>