A and B are two barrels of oil. The weight of oil in barrel A is 6.5 kg. If 1.5 kg of oil is poured from barrel B to barrel A, the weight of the two barrels is equal. How much is the original oil in barrel B?
甲、乙两桶油，甲桶油重6.5千克，如果从乙桶倒给甲桶1.5千克后，两桶油重量相等，乙桶原有油多少千克？
<gadget id="calculator">1.5 * 2</gadget>
<output>3</output>

<gadget id="calculator">6.5 + 3</gadget>
<output>9.5</output>

<result>9.5</result>