1. A,B,C,D,E五个人的薪水的median是20000,range不超过50000,其中A,B,C的薪水分别
是20000,40000,50000,问五个人薪水的平均值可能是多少?
(A) 20000
(B) 32000
(C) 18000
(D) 23000
(E) 31000
2. 一个样本在一个标准方差内的概率是0.68,两个标准方差内的概率是0.95. 一样本,m
ean=18.6,标准方差是6,求:该样本在6.6-12.6内占多少?
(A) 0
(B) 0.68
(C) 0.27
(D) 0.36
(E) 0.135
3. 一组数平均值9,标准方差2,另外一组数平均值3,标准方差1,问第一组数在(5,11)中的
数占总数的比例和第二组数在(1,4)中的数占总数的比例哪个大?
4. 有100个人都对A,B两个人进行评价,每个人只有两种选择,即好或不好,说A不好的有5
9个,说B不好的有65个,问:同时说AB都好的人数和35比较,哪个大?
5. 两个集合: A=[-1,-2,-3,-4] B=[-2,3,4,5],问B的A次方有多大的概率是正数?
(A) 0
(B) 0.5
(C) 0.625
(D) 0.875
(E) 0.135
6. 符合 X^2+Y^2<=100的整数解共有多少对?
7. Right triangle PQR is to be constructed in the xy-plane so that the right
angle is at P and PR is parrallel to the x-axis. The x-and y-coordinates of
P,Q,and R
are to be integers that satisfy the inequalities -4<=x<=5,6<=y<=16,how many
different triangles with these properties could be constructed?
(A) 110
(B) 1100
(C) 9900
(D) 10000
(E) 12100
8. A box contains 100 balls, numbered from 1 to 100. If three balls are sele
cted at random and with replacement from the box,what is the probability tha
t the
sum of the three numbers on the balls selected from the box will be odd?
(A) 1/4
(B) 3/8
(C) 1/2
(D) 5/8
(E) 3/4
9. (0-9) 要组成三位电话号码,第一位不能是0或1,三位数中相邻两位不能为同一数. (
e.g. 227 not acceptable,but 272 acceptable),求可以组成多少个这样的电话号
码?
10. 从1,2,3,4,5,6,7,8,9中选出三个数字组成一个三位数,这个三位数的digits中有两
个相同,另一个digit与其它两个都不同,问共有多少个这样的三位数?
(A) 72
(B) 144
(C) 180
(D) 216
(E) 54
11. A,B,C,D,E,F排在1,2,3,4,5,6六个位置上,问A不在1, B不在2, C不在3的情况下,共
有多少种排法?
(A) 720
(B) 450
(C) 180
(D) 216
(E) 320
12. 一直线L过点A(5,0), B(0,2), 坐标原点为O, 点P(X,Y)为三角形OAB中一点, 问:Y<
X的概率是多少?
(A) 1/4
(B) 3/8
(C) 1/2
(D) 5/8
(E) 3/4
13. If Bob can do a job in 20 days and Jane can do the job in 30 days, they
work together to do this job and in this period, Bob stop work for 2.5 days
and
Jane stop work for x days, and the job be finished for 14 days, what is x?
(A) 1.6
(B) 3.2
(C) 1.5
(D) 1.25
(E) 1.15
14. The probability of A is 60% and the probability of B is 50%, what is the
most possible probability that neither A nor B would happen?
(A) 0.80
(B) 0.40
(C) 0.75
(D) 0.55
(E) 0.68
15. In an insurance company, each policy has a paper record and an electric
record. For those policies having incorrect paper record, 60% also having
incorrect electric record; For policies having incorrect electric record, 75
% also having incorrect paper record. 3% of all policies have both incorrect
paper and
incorrect electric records. If we randomly pick out one policy,what's the pr
obability that the one having both correct paper and correct electric record
s?
(A) 0.80
(B) 0.94
(C) 0.75
(D) 0.88
(E) 0.92
16. There are 1200 respondents to a poll, each favoring their preference for
candidates A,B, and C. 54% favored A, 48% favored B, and 42% favored C, and
there is 30% favored both A and B. what's the largest possible number of res
pondents favoring C, but not C&B, nor C&A?
(A) 25%
(B) 30%
(C) 28%
(D) 38%
(E) 40%
7. Right triangle PQR is to be constructed in the xy-plane so that the right
angle is at P and PR is parrallel to the x-axis. The x-and y-coordinates of
P,Q,and R
are to be integers that satisfy the inequalities -4<=x<=5,6<=y<=16,how many
different triangles with these properties could be constructed?
(A) 110
(B) 1100
(C) 9900
(D) 10000
(E) 12100