There are 40 students in class 6 and 2, of which 55% are girls. How many girls are there?
六2班共有40人，其中女生占55%，女生有多少人？
<gadget id="calculator">55 / 100</gadget>
<output>11/20 = around 0.55</output>

<gadget id="calculator">40 * (11/20)</gadget>
<output>22</output>

<result>22</result>