300 students go to the spring outing, the first three cars each have 78 people, how many people should the fourth car have?
300同学们去春游，前3辆车每辆做78人，第四辆车该做多少人？
<gadget id="calculator">3 * 78</gadget>
<output>234</output>

<gadget id="calculator">300 - 234</gadget>
<output>66</output>

<result>66</result>