Girls in Class 1, Grade 6 account for 2/7 of the whole class, so how many girls are boys
六年级1班女生占全班人数的(2/7)，那么女生是男生人数的多少
<gadget id="calculator">2 / 7</gadget>
<output>2/7 = around 0.285714</output>

<gadget id="calculator">1 - (2/7)</gadget>
<output>5/7 = around 0.714286</output>

<gadget id="calculator">(2/7) / (5/7)</gadget>
<output>2/5 = around 0.4</output>

<result>2/5 = around 0.4</result>