A batch of goods was shipped, (1/3) was shipped for the first time, 5 tons were shipped for the second time, 40% was shipped for the third time, and there are 7 tons left. How many tons are there in this batch of goods?
运一批货物，第一次运了(1/3)，第二次运了5吨，第三次运了40%，还剩7吨，这批货物有多少吨？
<gadget id="calculator">5 + 7</gadget>
<output>12</output>

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

<gadget id="calculator">40 / 100</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 - (1/3) - (2/5)</gadget>
<output>4/15 = around 0.266667</output>

<gadget id="calculator">12 / (4/15)</gadget>
<output>45</output>

<result>45</result>