There are two containers A and B. The water in container A is twice the water in container B. If 8 liters of water are poured out from each container, then the water in container A is three times the water in container B. How many liters of water is in container B?
有甲、乙两个容器，甲容器中的水是乙容器中水的2倍，如果从每个容器中都倒出8升水，那么甲容器中的水是乙容器中水的3倍．乙容器原有水多少升？
<gadget id="calculator">8 * 3</gadget>
<output>24</output>

<gadget id="calculator">24 - 8</gadget>
<output>16</output>

<gadget id="calculator">3 - 2</gadget>
<output>1</output>

<gadget id="calculator">16 / 1</gadget>
<output>16</output>

<result>16</result>