A barrel of oil weighs 5 kg. After half of the oil is poured out, there are 3 kg left. What is the total weight of the poured oil?
一桶油连桶重5千克，倒出油的一半后，还剩3千克，共倒出的油重多少千克．
<gadget id="calculator">5 - 3</gadget>
<output>2</output>

<result>2</result>