A bag of rice is 50 kilograms, and (2/13) of it is eaten in the first week, how many kilograms are left.
一袋大米50千克，第一周吃掉了它的(2/13)，还剩多少千克．
<gadget id="calculator">2 / 13</gadget>
<output>2/13 = around 0.153846</output>

<gadget id="calculator">1 - (2/13)</gadget>
<output>11/13 = around 0.846154</output>

<gadget id="calculator">50 * (11/13)</gadget>
<output>550/13 = around 42.307692</output>

<result>550/13 = around 42.307692</result>