The school brought a pile of coal, burned (1/4) ton in the first quarter, burned (1/3) ton in the second quarter, and left (1/12) ton, how many tons is this pile of coal in total?
学校运来一堆煤，第一季度烧了(1/4)吨，第二季度烧了(1/3)吨，还剩(1/12)吨，这堆煤共多少吨？
<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">1 / 12</gadget>
<output>1/12 = around 0.083333</output>

<gadget id="calculator">(1/4) + (1/3) + (1/12)</gadget>
<output>2/3 = around 0.666667</output>

<result>2/3 = around 0.666667</result>