345 people came to the amusement park this morning, 168 people left at noon, and 243 people came in the afternoon. How many people are there in the amusement park now?
游乐园今天上午来了345人，中午离开168人，下午又来了243人，现在游乐园还有多少人？
<gadget id="calculator">345 - 168</gadget>
<output>177</output>

<gadget id="calculator">177 + 243</gadget>
<output>420</output>

<result>420</result>