A canteen burned (11/12) tons of coal in May, (2/7) of this pile of coal was burned in the first ten days, (1/9) of this pile of coal was burned in the middle ten days, and a fraction of this pile of coal was burned in the second ten days of the month Several?
某食堂5月份烧了(11/12)吨煤，上旬烧了这堆煤的(2/7)，中旬烧了这堆煤的(1/9)，下旬烧了这堆煤的几分之几？
<gadget id="calculator">2 / 7</gadget>
<output>2/7 = around 0.285714</output>

<gadget id="calculator">1 / 9</gadget>
<output>1/9 = around 0.111111</output>

<gadget id="calculator">(2/7) + (1/9)</gadget>
<output>25/63 = around 0.396825</output>

<gadget id="calculator">1 - (25/63)</gadget>
<output>38/63 = around 0.603175</output>

<result>38/63 = around 0.603175</result>