请高手确定答案

maymayfang

1。有5个正整数, 已知3,4,5,5一个未知, 问range是否大于2?

a average小于 median

b median=4

答案：a

2。both a and b are positive integers with three digits. the thousandth digit of a is 1 more than that of b, the tenth digit of a is 2 less than that of b, ask the difference between a/10－b/10?

答案：98

[此贴子已经被作者于2003-8-25 12:41:40编辑过]

uclb5550

Agree choice A.

The second question itself is not very clearly illustrated,is it? How about the hundredth and digit numbers? Are they all the same?

smart

1.答案a我觉得有点问题。
我选c。a、b两个数据一起可以解出该未知数不大于2。

smart

第2题题目有点问题。好象缺条件。

不知道答案98是如何得来的。

请指教。

uclb5550

只有1和2两个正整数满足条件A, so...

自尊宝

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1。有5个正整数, 已知3,4,5,5一个未知, 问range是否大于2?
a average小于 median
b median=4
答案：a
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denote x as the unkown integer,
1) when median=4, x = 1, 2, 3 range>2 or =2, so not correct.
2) average < median,
    a) x=1,2, median=4, average < median, range > 2;
    b) x=5,6,7, median = 5, average < median, range =2 or >2.

so answer should be E.

tony6

一道小题已知答案求助思路：3封不同的信，有4个信箱可供投递，共有多少种投信方法？答案是P3/4，C3/4，3的4次方，4的3次方。请各位大侠帮忙，谢谢。

atongmu

3^4
每封信有4种投法，用乘法原则。

tony6

每封信有4种投法是4的3次方，那3的4次方怎么解释？

sunny888

4的3次方