There are 120 boys in grade five, 20 more than girls, and girls account for the total number of grade five ((())/(())).
五年级男生有120人，比女生多20人，女生占五年级总人数的((())/(()))．
<gadget id="calculator">120 - 20</gadget>
<output>100</output>

<gadget id="calculator">100 + 120</gadget>
<output>220</output>

<gadget id="calculator">100 / 220</gadget>
<output>5/11 = around 0.454545</output>

<result>5/11 = around 0.454545</result>