There are 20 boys in Class 51, 5 fewer than girls. What percentage of the number of girls are boys?
五1班有男生20人，比女生少5人，男生占女生人数的几分之几？
<gadget id="calculator">20 + 5</gadget>
<output>25</output>

<gadget id="calculator">20 / 25</gadget>
<output>4/5 = around 0.8</output>

<result>4/5 = around 0.8</result>