For a batch of goods, 25% of the total amount was transported for the first time, and 20% of the total amount was transported for the second time. A total of 135 tons were transported for the two times. How many tons of this batch of goods are there in total?
一批货物，第一次运走总数的25%，第二次运走总数的20%，两次共运走135吨，这批货物一共多少吨？
<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">25 / 100</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">(1/5) + (1/4)</gadget>
<output>9/20 = around 0.45</output>

<gadget id="calculator">135 / (9/20)</gadget>
<output>300</output>

<result>300</result>