Two barrels of oil, A and B, each have several kilograms. If you want to pour the same amount of oil from barrel A as barrel B into barrel B, and then pour the same amount of oil from barrel B into barrel A, then the two The barrel of oil is exactly 36 kg. How many kilograms of oil is in barrel A?
甲乙两桶油各有若干千克，如果要从甲桶中倒出和乙桶同样多的油放入乙桶，再从乙桶倒出和甲桶同样多的油放入甲桶，这时两桶油恰好都是36千克．甲桶原来有油多少千克．
<gadget id="calculator">36 / 2</gadget>
<output>18</output>

<gadget id="calculator">36 - 18</gadget>
<output>18</output>

<gadget id="calculator">36 + 18</gadget>
<output>54</output>

<gadget id="calculator">54 / 2</gadget>
<output>27</output>

<gadget id="calculator">18 + 27</gadget>
<output>45</output>

<result>45</result>