A consignment team transports a batch of goods. The first day transports the goods (7/20), and the second day transports the rest (5/8). If the second day transports 18 tons more than the first day, So how many tons are there in total for this shipment?
一个运输队运一批货物，第一天运了这批货物的(7/20)，第二天运了余下的(5/8)，如果第二天比第一天多运了18吨，那么这批货物共有多少吨？
<gadget id="calculator">7 / 20</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">5 / 8</gadget>
<output>5/8 = around 0.625</output>

<gadget id="calculator">(13/20) * (5/8)</gadget>
<output>13/32 = around 0.40625</output>

<gadget id="calculator">(13/32) - (7/20)</gadget>
<output>9/160 = around 0.05625</output>

<gadget id="calculator">18 / (9/160)</gadget>
<output>320</output>

<result>320</result>