Question 1

The ages of students in a class have been put into the frequency distribution below.

What is the modal age of these students?

Select one:

a. 18

b. 20 

c. 19

d. 21

Question 2

The mean life of a particular brand of light bulb is 1000 hours and the standard deviation is 50 hours. It can be concluded that at least 75% of the bulbs will last between _______.

Select one:

a. 900 and 1100 hours

b. 950 and 1050 hours 

c. 800 and 1200 hours

d. 850 and 1150 hours

Question 3

If the median of a distribution is greater than mean, then the distribution is _________.

Select one:

a. not skewed

b. symmetrical about its mean

c. skewed to the right

d. skewed to the left 

Question 4

The lowest appropriate level of measurement for the median is _________.

Select one:

a. ratio

b. ordinal 

c. interval

d. nominal

Question 5

Which of the following is always true?

Select one:

a. The median is always one-half of the mean.

b. The mean is always equal to the median.

c. The mode is always greater than the mean.

d. The standard deviation is always the square root of the variance. 

Question 6

The average of the squared deviations from the arithmetic mean is called the _________.

Select one:

a. variance

b. mean absolute deviation

c. standard deviation.

d. coefficient of variation

Question 7

A sales manager has sampled past sales records to determine how many refrigerators are sold each day. Daily records for a sample of 10 days have been selected. The sales on these days are: 0, 4, 3, 2, 1, 3, 5, 5, 2, 5. What is the median daily sales?

Select one:

a. 3.5

b. 4

c. 3 

d. 2

Question 8

The mean life of a particular brand of light bulb is 1000 hours and the standard deviation is 50 hours. Tests show that the life of the bulb is approximately normally distributed. It can be concluded that approximately 68% of the bulbs will last between _______.

Select one:

a. 800 and 1200 hours

b. 950 and 1050 hours 

c. 850 and 1150 hours

d. 900 and 1100 hours

Question 9

Which of the following is an appropriate measure of central tendency for ordinal data?

Select one:

a. Coefficient of variation

b. Standard deviation.

c. Meadian 

d. Mean.

Question 10

The number of standard deviations that a value (X) is above or below the mean is the ______________.

Select one:

a. interquartile range

b. Z score 

c. coefficient of variation

d. absolute deviation

Question 11

A commuter travels many kilometres to work each morning. She has timed this trip 5 times during the last month. The time (in minutes) required to make this trip was 34, 39, 41, 35 and 41. The median time required for this trip was _______.

Select one:

a. 41

b. 37.5

c. 38 

d. 39

Question 12

A statistics student made the following grades on 5 tests: 84, 78, 88, 78 and 82. What is the mode?

Select one:

a. 88

b. 84

c. 80 

d. 78

Question 13

David Marshall, Human Resources Manager with Auckland First Bank (AFB), is reviewing the employee training programs of AFBs. His staff compiled the following table of regional statistics on teller training hours.

What can David conclude from these statistics?

Select one:

a. The southern distribution is skewed to the right.

b. The northern distribution is skewed to the left. 

c. The northern distribution is skewed to the right.

d. The southern distribution is skewed to the left.

Question 14

The empirical rule says that approximately what percentage of the values would be within

2 standard deviations of the mean in a bell-shaped set of data?

Select one:

a. 68%

b. Almost all.

c. 50%

d. 95%

Question 15

A sales manager has sampled past sales records to determine how many televisions are sold each day. Daily records for a sample of 5 days have been selected. The sales on these days are: 2, 4, 5, 2, 7. What is the mean for this set of data?

Select one:

a. 5

b. 4.5

c. 4 

d. 2

Question 16

The following box and whisker plot was constructed for the age of accounts receivable.

The box and whisker plot reveals that the accounts receivable ages are _______.

Select one:

a. not skewed

b. skewed to the right

c. skewed to the left 

d. normally distributed

Question 17

The notation 'x-bar' usually refers to the _______________.

Select one:

a. sample mean

b. sample variance 

c. population mean

d. population standard deviation

Question 18

David Marshall, Human Resources Manager with Auckland First Bank (AFB), is reviewing the employee training programs of AFBs. His staff compiled the following table of regional statistics on teller training hours.

What can David conclude from these statistics?

Select one:

a. The Northern distribution is skewed to the left. 

b. The Southern distribution is not skewed.

c. The Northern distribution has the greater relative dispersion.

d. The Southern distribution has the greater relative dispersion.

Question 19

In its Industry Norms and Key Business Ratios, Dun & Bradstreet reported that Q1, Q2 and Q3 for 577 motorcycle dealers' current ratios were 1.3, 1.6 and 2.9, respectively. From this we can conclude that __________________.

Select one:

a. 68% of these dealers had current ratios of 1.3 or less.

b. 50% of these dealers had current ratios of 1.6 or less.

c. 50% of these dealers had current ratios of 2.9 or more. 

d. 95% of these dealers had current ratios of 1.3 or more.

Question 20

In its Industry Norms and Key Business Ratios, Dun & Bradstreet reported that Q1, Q2 and Q3 for 577 motorcycle dealers' current ratios were 1.3, 1.6 and 2.9, respectively. From this we can conclude that __________________.

Select one:

a. 68% of these dealers had current ratios between 1.3 and 2.9.

b. 50% of these dealers had current ratios between 1.3 and 2.9. 

c. 75% of these dealers had current ratios between 1.3 and 2.9.

d. 95% of these dealers had current ratios between 1.3 and 2.9.