AMC 8 2004 Problem 11
AMC8 2004 年第 11 题
统计与数据图表★★★☆☆
Problem The numbers $-2, 4, 6, 9$ and 12 are rearranged according to these rules: 1. The largest isn't first, but it is in one of the first three places. 2. The smallest isn't last, but it is in one of the last three places. 3. The median isn't first or last. What is the average of the first and last numbers?
对－2，4，6，9 和 12 这些数按照如下规则重新排序： 最大的数不在第一个位置，但它位于前三个位置中的某个位置。 最小的数不在最后一个位置，但它位于后三个位置中的某个位置。 中位数不在第一个或者最后一个位置。 那么第一个数和最后一个数的平均值是多少？ Problem 12 Niki usually leaves her cell phone on. If her cell phone is on but she is not actually using it, the battery will last for hours. If she is using it constantly, the battery will last for only hours. Since the last recharge, her phone has been on hours, and during that time she has used it for minutes. If she doesn't talk any more but leaves the phone on, how many more hours will the battery last? Niki 的手机通常不关机。如果她的手机是开着的，但她实际上没有使用，那么电池将持续 24 小时。如果她一直使用手机，电池只能使用 3 个小时。自从最近一次充电以来，她的手机已经开机 9 小时，在这段时间里，她使用手机的时间是 60 分钟。如果她不再使用手机进行通话，而是让手机待机，那么电池还能用多少小时？
- A.3.5
- B.5
- C.6.5
- D.7.5
- E.8
正确答案 · Correct Answer
C
解析 · Solution
解析整理中
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