It takes three days to transport a pile of coal, 30% of the total is transported on the first day, 240 tons more than on the first day on the second day, and the ratio of the tons of coal transported on the second day to the third day is 9 : 5. How many tons is this pile of coal?
三天要运完一堆煤，第一天运了总数的30%，第二天运的比第一天多240吨，第二天和第三天所运的煤的吨数的比是9：5．这堆煤共有多少吨？
<gadget id="calculator">30 / 100</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">1 - (3/10)</gadget>
<output>7/10 = around 0.7</output>

<gadget id="calculator">9 + 5</gadget>
<output>14</output>

<gadget id="calculator">9 / 14</gadget>
<output>9/14 = around 0.642857</output>

<gadget id="calculator">(7/10) * (9/14)</gadget>
<output>9/20 = around 0.45</output>

<gadget id="calculator">(9/20) - (3/10)</gadget>
<output>3/20 = around 0.15</output>

<gadget id="calculator">240 / (3/20)</gadget>
<output>1_600</output>

<result>1_600</result>