There are 25 boys and 20 girls in Class 1, how many girls account for the whole class.
六一班有男生25人，女生20人，女生占全班人数的多少．
<gadget id="calculator">20 + 25</gadget>
<output>45</output>

<gadget id="calculator">20 / 45</gadget>
<output>4/9 = around 0.444444</output>

<result>4/9 = around 0.444444</result>