There is a barrel of oil, 30% of the full barrel is poured out for the first time, and 2 kg more than the first time is poured out for the second time, and there is still 6 kg in the barrel. How many kilograms of oil is in the barrel?
有一桶油，第一次倒出全桶的30%，第二次比第一次多倒出2千克，桶里还剩6千克，这桶油原来有多少千克？
<gadget id="calculator">6 + 2</gadget>
<output>8</output>

<gadget id="calculator">30 / 100</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">1 - (3/10) - (3/10)</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">8 / (2/5)</gadget>
<output>20</output>

<result>20</result>