A.1.1022

B.2

C.30

D.1.4847

正确答案：1.4847

3、A sample of 400 observations will be taken from an infinite population. The population proportion equals 0.8. The probability that the sample proportion will be greater than 0.83 is

A.0.4332

B. 0.9332

C.0.0668

D. 0.5668

正确答案：0.0668

4、A weighted average of the value of a random variable, where the probability function provides weights is known as

A.a probability function

B. a random variable

C.the expected value

D.random function

正确答案：the expected value

5、The student body of a large university consists of 60% female students. A random sample of 8 students is selected. What is the probability that among the students in the sample exactly two are female?

A.0.0896

B.0.2936

C.0.0413

D.0.0007

正确答案：0.0413

6、A.1.431

B.2.047

C.3.05

D. 21

正确答案：1.431

7、Exhibit 2 The following represents the probability distribution for the daily demand of computers at a local store.

A.0.7

B.0.3

C.0.4

D.1.0

正确答案：0.7

8、 If A and B are independent events, then

A. P(A) must be equal to P(B)

B.P(A) must be greater than P(B)

C.P(A) must be less than P(B)

D.P(A) must be equal to P(A│B)

正确答案：P(A) must be equal to P(A│B)

9、The purpose of statistical inference is to provide information about the

A.sample based upon information contained in the population

B.population based upon information contained in the sample

C.population based upon information contained in the population

D.mean of the sample based upon the mean of the population

正确答案：population based upon information contained in the sample

10、A theorem that allows us to use the normal probability distribution to approximate the sampling distribution of sample means and sample proportions whenever the sample size is large is known as the

A.approximation theorem

B.normal probability theorem

C.central limit theorem

D.central normality theorem

正确答案：central limit theorem

1、If two variables, X and Y, have a strong linear relationship, then

A.There may or may not be any causal relationship between X and Y

B.X causes Y to happen

C.Y causes X to happen

D.None of these alternatives is correct

正确答案：There may or may not be any causal relationship between X and Y