There are 45 students in Class 1 of the fifth grade, including 30 boys and girls ((())/(())).
五年级1班有共有45人，其中男生有30人，女生人数占全班人数的((())/(()))．
<gadget id="calculator">45 - 30</gadget>
<output>15</output>

<gadget id="calculator">15 / 45</gadget>
<output>1/3 = around 0.333333</output>

<result>1/3 = around 0.333333</result>