There are 24 boys in a class, accounting for 4/7 of the whole class. How many girls are there in this class?
某班男生有24人，占全班人数的(4/7)，该班女生有多少人．
<gadget id="calculator">4 / 7</gadget>
<output>4/7 = around 0.571429</output>

<gadget id="calculator">24 / (4/7)</gadget>
<output>42</output>

<gadget id="calculator">42 - 24</gadget>
<output>18</output>

<result>18</result>