There were originally 680 people on the train, 258 people went down after arriving in Changsha, and 189 people got on again. How many people are there on the train now?
火车上原有680人，到长沙后下去了258人，又上来了189人，火车上现在有多少人？
<gadget id="calculator">680 - 258</gadget>
<output>422</output>

<gadget id="calculator">422 + 189</gadget>
<output>611</output>

<result>611</result>