A professional fish farmer sold the fish he raised to the market three times last year. 35% of the total was sold for the first time, the rest (8/13) was sold for the second time, and 720 kg less than the first time was sold for the third time. How many kilograms of fish did this professional fish farmer sell in total?
某养鱼专业户去年分三次把所养的鱼卖给菜场．第一次卖去总数的35%，第二次卖去余下的(8/13)，第三次卖去的比第一次卖去的少720千克．这个养鱼专业户共卖鱼多少千克？
<gadget id="calculator">35 / 100</gadget>
<output>7/20 = around 0.35</output>

<gadget id="calculator">1 - (7/20)</gadget>
<output>13/20 = around 0.65</output>

<gadget id="calculator">8 / 13</gadget>
<output>8/13 = around 0.615385</output>

<gadget id="calculator">(13/20) * (8/13)</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 - (7/20) - (2/5)</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">(7/20) - (1/4)</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">720 / (1/10)</gadget>
<output>7_200</output>

<result>7_200</result>