2008 AMC 8 第 9 题
先试着解答 2008 AMC 8 第 9 题，然后核对你的答案与精心整理的解答，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 2008 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。
9.
年，投资大亨塔米投入了 ，为期两年。第一年她的投资亏损 ，但第二年剩余投资增长了 。这两年内塔米的投资变化是多少？
In Tycoon Tammy invested for two years. During the first year her investment suffered a loss, but during the second year the remaining investment showed a gain. Over the two-year period, what was the change in Tammy’s investment?
亏损
loss
亏损
loss
增长
gain
增长
gain
增长
gain
答案：D
小提示：
亏损 后，剩下原投资的
After a loss, of the original investment remains.
大提示：
把 的增长作用在减少后的金额上，而不是原金额上
Apply the gain to the reduced amount, not to the original amount.
解答：
的亏损使投资从 变为 。
的增长再使其变为 。
投资从 变为 ，也就是增长 。
所以正确答案是 D。
The loss changes the investment from to .
The gain then changes it to .
The investment went from to , which is a gain.
Thus, D is the correct answer.
其他年份的第 9 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
- 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
- 2025 AMC 8
- 2026 AMC 8