A car dealership planned to sell 600 cars in the whole year last year, but actually sold 75 cars per month on average. How many more cars were sold in the whole year than planned?
一个汽车专卖店去年计划全年销售600辆汽车，实际平均每个月销售75辆，实际全年比计划多销售多少辆？
<gadget id="calculator">75 * 12</gadget>
<output>900</output>

<gadget id="calculator">900 - 600</gadget>
<output>300</output>

<result>300</result>