For a pile of goods, 1/5 of the total amount was shipped on the first day, and 15 tons more than on the first day were shipped on the second day, leaving 45 tons of goods undelivered. How many tons are there in this pile of goods?
一堆货物，第一天运了总数的(1/5)，第二天比第一天多运了15吨，还剩45吨货物没运，这堆货物共有多少吨？
<gadget id="calculator">15 + 45</gadget>
<output>60</output>

<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 - (1/5) - (1/5)</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">60 / (3/5)</gadget>
<output>100</output>

<result>100</result>