A bag of rice weighs 20 kilograms, ate 6 kilograms in the first week, and 7 kilograms in the third week. How much of this bag of rice is left?
一袋大米重20千克，第一周吃了6千克，第三周吃了7千克．还剩下这袋大米的几分之几？
<gadget id="calculator">20 - 6 - 7</gadget>
<output>7</output>

<gadget id="calculator">7 / 20</gadget>
<output>7/20 = around 0.35</output>

<result>7/20 = around 0.35</result>