Pour 5 cups of water into a bucket, and the weight of the bucket is 3 kg. Pour 8 cups of water, and the weight of the bucket is 4 kg, 200 grams. How much does the bucket weigh?
往一个桶里倒入5杯水，连桶重3千克，倒入8杯水，连桶重4千克200克，这个桶多重？
<gadget id="calculator">4.2 - 3</gadget>
<output>1.2</output>

<gadget id="calculator">8 - 5</gadget>
<output>3</output>

<gadget id="calculator">1.2 / 3</gadget>
<output>0.4</output>

<gadget id="calculator">0.4 * 5</gadget>
<output>2</output>

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

<result>1</result>