The number of boys accounts for the whole class (5/12), and the number of girls is equal to the number of boys.
男生人数占全班的(5/12)，女生人数相当于男生人数的多少．
<gadget id="calculator">5 / 12</gadget>
<output>5/12 = around 0.416667</output>

<gadget id="calculator">1 - (5/12)</gadget>
<output>7/12 = around 0.583333</output>

<gadget id="calculator">(7/12) / (5/12)</gadget>
<output>7/5 = around 1.4</output>

<result>7/5 = around 1.4</result>