Question

For each question, encircle the correct answer.

6 )In a population of 100 items where 20 items are defective. A sample of 40 items has been selected randomly from the population and 10 of the them are defective. The sampling error of the proportion is

A) 0.05

B) 0.2

C) 0.25

D) 1

7 )If a population has a highly skewed distribution, which of the following sample sizes is more likely to be sufficiently large that the distribution of the sample means will be approximately normal?

A) n=5

B) n=13

C) n=21

D) n=34

8) Suppose Jarir bookstore can expect five customers every three minutes, on average. In an 18 minutes period, what is the expected number of customers who will enter Jarir ?

A) 21.

B) 23.

C) 30.

D) 33.

9) Increasing the sample size_________ the margin of error.

A) increases

B) decreases

C) cancels

D) does not affect

10) If the population is normally distributed. The distribution of the sample means is approximately

A) Binomial

B) Exponential

C) Uniform

D) Normal

Answer 1

6)In a population of 100 items where 20 items are defective. A sample of 40 items has been selected randomly from the population and 10 of the them are defective.

The sampling error of the proportion =

7)For a sample to be extremely normal,n should be greater than 30.

If a population has a highly skewed distribution, For sample size=34 lais sufficientlyrge that the distribution of the sample means will be approximately normal.

8) Suppose Jarir bookstore can expect five customers every three minutes, on average. In an 18 minutes period, the expected number of customers who will enter Jarir =

9) Increasing the sample size decreases the margin of error.

10)If the population is normally distributed. The distribution of the sample means is approximately normal.