A city bus station, starting from 7:00 in the morning, sends out a bus every 10 minutes, and leaves the last bus at 9:00 pm. How many cars were there in total on this day?
一市内公共汽车站，从早晨7时开始发车以后，每10分钟发一辆车，到晚上9时发出最后一辆车．这一天共发车多少辆？
<gadget id="calculator">840 / 10</gadget>
<output>84</output>

<gadget id="calculator">84 + 1</gadget>
<output>85</output>

<result>85</result>