Mom bought a barrel of salad oil weighing 5kg, and ate 400g a day. After a week, how many grams of salad oil was reduced?
妈妈买了一桶色拉油重5kg，每天吃400g，一周后，色拉油减少了多少克．
<gadget id="calculator">400 * 7</gadget>
<output>2_800</output>

<result>2_800</result>