A barrel of gasoline, pour out its (2/5) for the first time, pour out 10 kilograms for the second time, and there are 10 kilograms left in the barrel, how much does the whole barrel weigh?
一桶汽油，第一次倒出它的(2/5)，第二次倒出10千克，桶里还剩10千克，问全桶油重多少千克？
<gadget id="calculator">10 + 10</gadget>
<output>20</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">20 / (3/5)</gadget>
<output>100/3 = around 33.333333</output>

<result>100/3 = around 33.333333</result>