There were originally 96 cars in a parking lot, but 28 cars were driven out and several cars were driven in. At this time, there were 78 cars in the parking lot. How many cars did you drive in?
一个停车场原有汽车96辆，后来开出了28辆，开进若干辆，这时停车场有汽车78辆．开进多少辆汽车？
<gadget id="calculator">96 - 28</gadget>
<output>68</output>

<gadget id="calculator">78 - 68</gadget>
<output>10</output>

<result>10</result>