【问题目】精讲精练题目

艾向阳

                                                                                                                                                大神们，我在这里请教大家一点题目......，如下：
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[size=12.000000pt]71.
[size=12.000000pt]The three-digit integer [size=12.000000pt]kss [size=12.000000pt]is the sum of the two-digit integers [size=12.000000pt]ks [size=12.000000pt]and [size=12.000000pt]rs[size=12.000000pt], where [size=12.000000pt]k[size=12.000000pt], [size=12.000000pt]r[size=12.000000pt], and s are the digits of the integers. Which of the following must be true?



                                                                                                [size=12.000000pt] I. [size=12.000000pt]k[size=12.000000pt]=2
[size=12.000000pt] II. [size=12.000000pt]r[size=12.000000pt]=9
III. s=5
      
A. I only
B.II only
C. III only
D. I and II
E.II and III


答案: B

                                                                                                [size=12.000000pt]

[size=12.000000pt]87.[size=12.000000pt](5Q3)
[size=12.000000pt]If a committee of 3 people is to be selected from among 5 married couples so that thecommittee does not include two people who are married to each other, how manysuch committees are possible?
                                        [size=12.000000pt]A. 20B. 40C. 50D. 80E. 120
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[size=12.000000pt]答案：D
                               
                       
               



                                                                                                [size=12.000000pt]90.[size=12.000000pt](8Q9)
[size=12.000000pt]If an integer [size=12.000000pt]n [size=12.000000pt]is to be chosen at random from the integers 1 to 96, inclusive, what isthe probability that [size=12.000000pt]n[size=12.000000pt]([size=12.000000pt]n [size=12.000000pt]+ 1)([size=12.000000pt]n [size=12.000000pt]+ 2) will be divisible by 8?
                                        答案：5/8
                               
                       
               



                                                                                                [size=12.000000pt]91.
On a race track a maximum of 5 horses can race together at a time. There are a total of25 horses. There is no way of timing the races. What is the minimum number of raceswe need to conduct to get the top 3 fastest horses?
                                        [size=12.000000pt]A. 5B. 7C. 8D. 10E. 11
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[size=12.000000pt]答案：B
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一抹斜阳

卤煮重新编辑下帖子吧，伤眼睛。。