After A bag of rice (2/7) is given to B bag, the two bags of rice are the same, so B belongs to A ((())/(())).
甲袋大米的(2/7)给乙袋后，两袋大米同样多，原来乙是甲的((())/(()))．
<gadget id="calculator">2 / 7</gadget>
<output>2/7 = around 0.285714</output>

<gadget id="calculator">1 - (2/7) - (2/7)</gadget>
<output>3/7 = around 0.428571</output>

<gadget id="calculator">(3/7) / 1</gadget>
<output>3/7 = around 0.428571</output>

<result>3/7 = around 0.428571</result>