2025 AMC 8 第 14 题
先试着解答 2025 AMC 8 第 14 题，然后核对你的答案与视频与精心整理的解答，解答来自 LIVE by Po-Shen Loh。你也可以参加完整限时模拟考试、查看全部 2025 AMC 8 解答，或核对答案。
所有题目均经美国数学协会（MAA）官方合法授权使用。
14.
一个数 被插入列表 、、、、 中。现在平均数是中位数的两倍。 是多少？
A number is inserted into the list The mean is now twice as great as the median. What is
小提示：
因为每个选项都至少为 ，中位数保持不变
Since every choice is at least the median stays fixed
大提示：
令总和等于 乘以中位数的两倍
Make the total sum equal to times twice the median
视频讲解：
Click to load, then click again to play
文字解答：
插入 后共有 个数。个数为偶数，所以中位数是中间两个数的平均。
所有选项都至少为 ，所以插入后中间两个数仍是 和 。方便的是，无论选哪个选项，中位数都是 。
平均数是中位数的两倍，即 。
要让 个数的平均数为 ，总和必须为 。
原来 个数的和为 所以答案是 ，选 E。
After inserting into the list, there will be total numbers. That is even, so the median will be the average of the middle two numbers.
All of the answer choices are at least so when they are inserted into the list, the middle two numbers will be and It is convenient that the median will always be no matter which answer choice is picked.
The mean becomes twice the median, which is
To have a total of numbers with mean their sum must become
The sum of the original numbers is so the answer is which is choice E.
其他年份的第 14 题
- 1985 AMC 8
- 1986 AMC 8
- 1987 AMC 8
- 1988 AMC 8
- 1989 AMC 8
- 1990 AMC 8
- 1991 AMC 8
- 1992 AMC 8
- 1993 AMC 8
- 1994 AMC 8
- 1995 AMC 8
- 1996 AMC 8
- 1997 AMC 8
- 1998 AMC 8
- 1999 AMC 8
- 2000 AMC 8
- 2001 AMC 8
- 2002 AMC 8
- 2003 AMC 8
- 2004 AMC 8
- 2005 AMC 8
- 2006 AMC 8
- 2007 AMC 8
- 2008 AMC 8
- 2009 AMC 8
- 2010 AMC 8
- 2011 AMC 8
- 2012 AMC 8
- 2013 AMC 8
- 2014 AMC 8
- 2015 AMC 8
- 2016 AMC 8
- 2017 AMC 8
- 2018 AMC 8
- 2019 AMC 8
- 2020 AMC 8
- 2022 AMC 8
- 2023 AMC 8
- 2024 AMC 8
- 2026 AMC 8