A barrel of oil, pour out 2/5 of it for the first time, then pour 60 kilograms back into the barrel, pour out 3/8 of the oil in the barrel for the second time, and pour out 130 kilograms for the third time, then there is still 60 kilograms in the barrel There are 20 kilograms left, how many kilograms are there in this barrel of oil?
一桶油，第一次倒出它的2/5，然后倒回桶内60千克，第二次倒出桶中油的(3/8)，第三次倒出130千克，这时桶中还剩下20千克，求原来这桶油有多少千克？
<gadget id="calculator">130 + 20</gadget>
<output>150</output>

<gadget id="calculator">3 / 8</gadget>
<output>3/8 = around 0.375</output>

<gadget id="calculator">1 - (3/8)</gadget>
<output>5/8 = around 0.625</output>

<gadget id="calculator">150 / (5/8)</gadget>
<output>240</output>

<gadget id="calculator">240 - 60</gadget>
<output>180</output>

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

<gadget id="calculator">1 - (2/5)</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">180 / (3/5)</gadget>
<output>300</output>

<result>300</result>