Fill a bucket with water, double the original volume, and the bucket will weigh 10 kilograms. If you add 5 times the original volume, the bucket will weigh 22 kilograms. How many kilograms of water is in the bucket?
用一只水桶装水，把水加到原来的2倍，连桶重10千克，如果把水加到原来的5倍，连桶重22千克．桶里原有水多少千克？
<gadget id="calculator">22 - 10</gadget>
<output>12</output>

<gadget id="calculator">5 - 2</gadget>
<output>3</output>

<gadget id="calculator">12 / 3</gadget>
<output>4</output>

<result>4</result>