Li Zhuang harvested 7,500 kilograms of wheat on the first day, 3,820 kilograms of wheat in the morning of the second day, and 4,080 kilograms of wheat in the afternoon. How much more wheat was harvested on the second day than on the first day?
李庄第一天收小麦7500千克，第二天上午收小麦3820千克，下午收小麦4080千克，第二天比第一天多收小麦多少千克？
<gadget id="calculator">3_820 + 4_080</gadget>
<output>7_900</output>

<gadget id="calculator">7_900 - 7_500</gadget>
<output>400</output>

<result>400</result>