A toy factory planned to produce 840 sets of toys in 30 days, but actually completed it in 24 days. How many sets were actually produced per day more than planned?
某玩具厂计划30天生产玩具840套，实际24天就完成了，实际比计划每天多生产多少套？
<gadget id="calculator">840 / 24</gadget>
<output>35</output>

<gadget id="calculator">840 / 30</gadget>
<output>28</output>

<gadget id="calculator">35 - 28</gadget>
<output>7</output>

<result>7</result>