There are two bags of rice, A and B. Bag A weighs 50 kilograms. Bag A is used (2/5) and bag B is used (1/4). The rest of the two bags weigh the same.
甲、乙两袋大米，甲袋大米重50千克，甲袋用去(2/5)，乙袋用去(1/4)，两袋剩下的一样重，乙袋原有大米多少千克？
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 - (2/5)</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 - (1/4)</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">(3/5) / (3/4)</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">50 * (4/5)</gadget>
<output>40</output>

<result>40</result>