1. A sample of size 10 gave a sample mean of 170 and a sample standard deviation of 25.50.

The 90% confidence interval for the population mean is

I. 170 18.2403

I. 170 14.7810

III. 170 17.9662

IV. 170 14.1617

QUESTION 2

If a sample of size 100 is taken from a population with astandard deviation of50,what is the value of the standard error of mean?

I. 5.00

II. 0.50

III. 2.00

IV. 0.71

QUESTION 3

The difference between the parameter and a sample statistic is called

I. Sampling units

II. Sampling error

III. Sampling frame

IV. Probability

QUESTION 4

Which of the following is NOT a parameter?

I. Population mean,

II. Sample mean,

III. Population variance,

IV. Population proportion of successes,p_s

QUESTION 5

Which of the following Z value would be used to construct a 96%confidence interval for the population proportion?

I. 2.054

II. 0.8315

III. 0.5160

IV. 1.751

QUESTION 6

Which of the following t value would be used to construct a 90%confidence interval for mean with a sample of size n = 15?

I 1.753

II. 1.345

III. 1.341

IV. 1.761

QUESTION 7

Out of a sample of 50 students, 30 of them wear contact lenses.

The 95% confidence interval for the proportion of all students who wears contact lenses is

I. 0.4 0.11397

II. 0.6 0.11397

III. 0.60.13579

IV. 0.4 0.13579

QUESTION 8

The heights of male students from a college are normally distributed with a mean of 168cm and a standard deviation of 4.5cm.

If a sample of 5 students is selected, what is the probability that the mean height is more than 170cm?

I. 0.9938

II. 0.8399

III. 0.6714

IV. 0.1601

QUESTION 9

6% of the residents in city A are color blind.

What is the probability that out of a random sample of 120 residents from city A,less than 10%of them are color blind?

I. 0.0325

II. 0.1550

III. 0.8450

IV. 0.9675

QUESTION 10

For Student t distribution, the degrees of freedom (df) is determined by

I. n

II. N

III. n - 1

IV. n + 1