A transport team plans to transport a batch of goods within 3 days. On the first day, 7.2 tons were shipped, and the second day was 70% less than the total tonnage of this batch of goods. The ratio of the second day to the third day was 3:5. How many tons is the cargo?
某运输队计划在3天内运完一批货物．第一天运走7.2吨，第二天运的比这批货物的总吨数少70%，第二天运的与第三天运的吨数的比是3：5，第二天运的货物是多少吨？
<gadget id="calculator">70 / 100</gadget>
<output>7/10 = around 0.7</output>

<gadget id="calculator">1 - (7/10)</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">36 * (3/10)</gadget>
<output>54/5 = around 10.8</output>

<result>54/5 = around 10.8</result>