There is 35 liters of water in bucket A, and 13 liters of water in bucket B. How many liters of water in bucket A can be poured into bucket B so that the water in bucket A is twice the amount of water in bucket B.
甲桶有水35升，乙桶有水13升，甲桶的水倒入乙桶多少升，才能使甲桶的水是乙桶的2倍．
<gadget id="calculator">35 + 13</gadget>
<output>48</output>

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

<gadget id="calculator">48 / 3</gadget>
<output>16</output>

<gadget id="calculator">16 - 13</gadget>
<output>3</output>

<result>3</result>