Question 1

Which of the following best describes the variable 'make of car' (e.g., Honda, Ford, Toyota) recorded by a researcher from 200 commuters?

Accepted Answer

Qualitative

Question 2

A survey records the number of emails a person receives in a day. This variable is best classified as:

Accepted Answer

Quantitative and discrete

Question 3

Class rank (1st, 2nd, 3rd, ...) is measured at which level of measurement?

Accepted Answer

Ordinal

Question 4

A school has 1,200 students. A survey of 60 randomly selected students found that 55% support a new dress code. The value 55% is a:

Accepted Answer

Statistic, because 60 students is a sample

Question 5

A researcher numbers all 5,000 employees at a company and uses a computer to randomly select 200 of them. This is an example of:

Accepted Answer

Simple random sampling

Question 6

A researcher randomly selects 8 entire apartment buildings out of 120 in a city, then surveys every resident in those 8 buildings. This is an example of:

Accepted Answer

Cluster sampling

Question 7

A histogram of test scores shows most students scoring high, with a small tail of low scores stretching toward 0. This distribution is:

Accepted Answer

Skewed left

Question 8

A distribution of test scores is approximately symmetric with no outliers. Which measure of central tendency would be the most appropriate?

Accepted Answer

Mean

Question 9

A distribution is perfectly symmetric and unimodal. Which statement is likely true?

Accepted Answer

Mean = Median = Mode

Question 10

If a data set contains 10,000 values arranged in ascending order, which formula identifies the values used to calculate the median?

Accepted Answer

Average positions $$n/2$$ and $$(n/2)+1$$

Question 11

A small business has 8 employees with the following ages: 22, 24, 24, 27, 30, 31, 45, 58. What is the mean age? (Round to two decimal places.)

Accepted Answer

$$32.63$$

Question 12

Data ranges from a minimum of 15 to a maximum of 88, and you want to build a frequency distribution with 6 classes. What is the class width?

Accepted Answer

$$13$$

Question 13

A group of 5 friends has the following weekly grocery spending: $$40, 45$$, $$45, 50$$, $220. Compute the sample mean.

Accepted Answer

$$80$$

Question 14

The mean of the following data set is 20: 10, 30, 4, 36, x. What is the value of x?

Accepted Answer

$$20$$

Question 15

A survey of 40 households recorded the number of cars owned: 0 (3 households), 1 (18 households), 2 (14 households), 3 (5 households). What is the relative frequency for households owning 2 cars? (Round to two decimal places.)

Accepted Answer

$$0.35$$

Question 16

Refer to the histogram of Yelp ratings for Hot Doug’s. Which rating category had the highest frequency?

Accepted Answer

5 Stars

Question 17

Refer to the USA Today-type graph of ways to save for college. Why might this graph be considered misleading?

Accepted Answer

The visual sizes of the symbols exaggerate differences and lack a clear scale

Question 18

Refer to the histogram of time spent completing an assignment. Which measure of central tendency best describes the center of the distribution, and why?

Accepted Answer

Median, because the distribution is skewed right and the median is resistant to outliers

Question 19

Which of the following is a reason why the mean is not a resistant statistic, but the median is?

Accepted Answer

The mean uses every value in its calculation, so outliers can pull it substantially

Introductory Statistics Practice Test – Step-by-Step Study Guidance

Guida di studio - Domande di pratica

Study guide - Flashcard