For a pile of coal, (2/7) was removed in the morning, and (1/3) was removed in the afternoon, and there were 6 tons more, and finally 14 tons were left undelivered. How many tons did this pile of coal have?
一堆煤，上午运走了它的(2/7)，下午运走了它的(1/3)还多6吨，最后剩下14吨没运，这堆煤原有多少吨？
<gadget id="calculator">6 + 14</gadget>
<output>20</output>

<gadget id="calculator">2 / 7</gadget>
<output>2/7 = around 0.285714</output>

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

<gadget id="calculator">(2/7) + (1/3)</gadget>
<output>13/21 = around 0.619048</output>

<gadget id="calculator">1 - (13/21)</gadget>
<output>8/21 = around 0.380952</output>

<gadget id="calculator">20 / (8/21)</gadget>
<output>105/2 = around 52.5</output>

<result>105/2 = around 52.5</result>