Statistics and Probability Quizzes: Test Your Skills

Question 1

In a dataset, the mean is 10 and the standard deviation is 2. Which of the following is most likely to be true about the data?

Accepted Answer

Most data values fall between 8 and 12

Answer

Half of the data values are less than 10.

Answer

The data values are spread out over a wide range.

Answer

The dataset has many outliers.

Question 2

Which measure of central tendency is least affected by extreme values?

Accepted Answer

Median

Answer

Mean

Answer

Mode

Answer

Range

Question 3

What is a key characteristic of non-parametric tests?

Accepted Answer

They can be used when the data is not normally distributed.

Answer

They assume the data follows a specific distribution.

Answer

They are generally more powerful than parametric tests.

Answer

They require a large sample size to be effective.

Question 4

What is a potential limitation of using a non-probability sampling method?

Accepted Answer

It may produce biased results.

Accepted Answer

It may be difficult to generalize the findings to the entire population.

Answer

It may require more time than probability sampling.

Question 5

A bag contains 5 red marbles, 3 blue marbles, and 2 green marbles. What is the probability of drawing a blue marble?

Accepted Answer

1 in 3

Answer

1 in 5

Answer

1 in 2

Answer

2 in 3

Question 6

A survey of 100 students found that the average height is 68 inches, with a standard deviation of 5 inches. What is the z-score for a student who is 72 inches tall?

Accepted Answer

0.8

Answer

0.4

Answer

1.2

Answer

1.6

Question 7

Which of the following is a measure of central tendency that represents the most frequently occurring value in a dataset?

Accepted Answer

Mode

Answer

Mean

Answer

Median

Answer

Standard deviation

Question 8

A store sells bananas for 30 cents each. If the probability of selling a banana on any given day is 0.6, what is the expected revenue from selling bananas on a day?

Accepted Answer

18

Answer

0.6

Answer

3

Answer

30

Question 9

A fair coin is flipped three times. What is the probability of getting heads all three times?

Accepted Answer

0.125

Answer

0.25

Answer

0.5

Answer

0.75

Question 10

Which of the following is an example of a discrete random variable?

Accepted Answer

The number of students in a classroom

Answer

The temperature in a room

Answer

The height of a person

Answer

The time it takes to complete a task

Question 11

For a skewed distribution, which measure of central tendency is most appropriate?

Accepted Answer

Median

Answer

Mean

Answer

Mode

Question 12

A fair coin is flipped three times. What's the probability of getting exactly two heads?

Accepted Answer

1/8

Answer

1/2

Answer

1/4

Question 13

Which example illustrates mutually exclusive events?

Accepted Answer

Drawing a red card and an ace from a deck of cards

Answer

Rolling a 6 and an even number on a dice

Answer

Getting a promotion and winning the lottery

Question 14

A bag contains 5 red and 7 blue marbles. What's the probability of selecting a red marble?

Accepted Answer

5/12

Answer

1/2

Answer

7/12

Question 15

What's the purpose of a confidence interval?

Accepted Answer

Estimating population parameters

Answer

Predicting future outcomes

Answer

Hypothesis testing

Question 16

Which variable is considered discrete?

Accepted Answer

Number of siblings in a family

Answer

Height of students in a classroom

Answer

Temperature in a city over a week

Answer

Speed of a car on a highway

Question 17

Which factor does NOT influence the standard deviation of a data set?

Accepted Answer

Data type (quantitative/qualitative)

Answer

Data spread

Answer

Number of data points

Answer

Outliers

Question 18

Which graph is suitable for displaying a categorical variable?

Accepted Answer

Bar chart

Answer

Stem-and-leaf plot

Answer

Histogram

Answer

Scatter plot

Question 19

Which of the following measures the statistical center of a dataset?

Accepted Answer

Mean

Answer

Range

Answer

Standard deviation

Answer

Variance

Question 20

What is the likelihood of rolling a 6 on a standard six-sided die?

Accepted Answer

1/6

Answer

1/3

Answer

1/4

Answer

1/8

Question 21

How can a population be distinguished from a sample?

Accepted Answer

A population is the entire group under investigation, while a sample is a subset of that group.

Answer

A sample is the entire group under investigation, while a population is a subset of that group.

Answer

A population is a group of objects, while a sample is a set of data.

Answer

A population is a theoretical concept, while a sample is a real-world observation.

Question 22

What is the probability of drawing a red card from a deck containing 26 red cards and 26 black cards?

Accepted Answer

1/2

Answer

1/4

Answer

1/8

Answer

1/16

Question 23

Which of the following experiments involves repeated, independent trials with only two possible outcomes?

Accepted Answer

Flipping a coin

Answer

Rolling a die

Answer

Drawing a card from a deck

Answer

Measuring the height of a person

Question 24

Which of the following statistical measures does NOT summarize the typical value of a dataset?

Accepted Answer

Range

Answer

Mean

Answer

Median

Answer

Mode

Question 25

Which probability distribution is symmetrical around its mean?

Accepted Answer

Normal distribution

Answer

Binomial distribution

Answer

Poisson distribution

Answer

Exponential distribution

Question 26

Which sampling technique ensures that each individual in the population has an equal chance of being selected?

Accepted Answer

Simple random sampling

Answer

Stratified sampling

Answer

Cluster sampling

Answer

Systematic sampling

Question 27

Which of the following is not a measure of central tendency?

Accepted Answer

Range

Answer

Mean

Answer

Median

Answer

Mode

Question 28

A survey of 100 individuals revealed that 60% own a smartphone. What is the probability that a randomly selected individual from the survey owns a smartphone?

Accepted Answer

0.6

Answer

0.4

Answer

0.75

Answer

0.25

Question 29

Which distribution is characterized by a bell-shaped curve?

Accepted Answer

Normal distribution

Answer

Skewed distribution

Answer

Uniform distribution

Answer

Bimodal distribution

Question 30

Expected value, a measure of central tendency for a probability distribution, represents the:

Accepted Answer

average value we expect to occur

Answer

most likely value to occur

Answer

minimum possible value that can occur

Question 31

Which of the following is **not** an assumption required for linear regression analysis?

Accepted Answer

Absence of outliers

Answer

Linear relationship between variables

Answer

Constant variance of residuals (homoscedasticity)

Answer

Independence of observations

Question 32

In a dataset, the value of 200 is significantly higher than the rest. Which measure of central tendency is most affected by this outlier?

Accepted Answer

Mean

Answer

Median

Answer

Mode

Question 33

Which type of sampling bias occurs when a study excludes a specific group of individuals?

Accepted Answer

Undercoverage bias

Answer

Non-response bias

Answer

Selection bias

Answer

Measurement bias

Question 34

Which of the following is not a measure of central tendency?

Accepted Answer

Standard deviation

Answer

Mean

Answer

Median

Answer

Mode

Question 35

A scatterplot of two variables shows a linear relationship. Which of the following statistical measures can be used to describe this relationship?

Accepted Answer

Both of the above

Answer

Correlation coefficient

Answer

Regression line

Answer

Neither of the above

Question 36

Which of the following accurately describes the relationship between correlation and causation?

Accepted Answer

Causation implies correlation, but correlation does not necessarily imply causation.

Answer

Correlation always indicates causation.

Answer

Correlation and causation have the same meaning.

Question 37

A survey of 100 students found that their average height was 5 feet 6 inches. Which measure of central tendency does this represent?

Accepted Answer

Mean

Answer

Median

Answer

Mode

Answer

Range

Question 38

A survey of 300 adults found that 150 of them have a college degree. What is the sample size for this survey?

Accepted Answer

300

Answer

150

Answer

450

Answer

600

Question 39

A data set has a mean of 12 and a range of 8. What is the minimum value in the data set?

Accepted Answer

4

Answer

8

Answer

10

Answer

12

Question 40

Which measure is not a measure of central tendency used to describe a data set?

Accepted Answer

Range

Answer

Mean

Answer

Median

Answer

Mode

Question 41

In a survey, 100 students reported studying an average of 10 hours per week. What is the total number of hours spent studying by all 100 students?

Accepted Answer

1000

Answer

500

Answer

200

Answer

100

Question 42

A bag contains 5 red and 7 blue balls. If a ball is drawn at random, what is the probability of drawing a blue ball?

Accepted Answer

7/12

Answer

5/12

Answer

2/5

Answer

1/2

Question 43

Which measure best describes the spread or variability of a data set?

Accepted Answer

Standard deviation

Answer

Mean

Answer

Range

Answer

Median

Question 44

Which of the following is a measure of central tendency that represents the value that appears most frequently in a data set?

Accepted Answer

Mode

Answer

Range

Answer

Median

Answer

Mean

Question 45

Which of the following is a characteristic of a binomial distribution?

Accepted Answer

Discrete distribution

Answer

Uniform distribution

Answer

Continuous distribution

Answer

Normal distribution

Question 46

What is the probability of selecting a vowel from the English alphabet?

Accepted Answer

5/26

Answer

1/6

Answer

1/5

Answer

1/4

Question 47

Students studied for a test for these amounts of time: 2 hours, 3 hours, 4 hours, 5 hours, 6 hours, 7 hours, and 8 hours. What is the median study time?

Accepted Answer

5 hours

Answer

6 hours

Answer

4 hours

Answer

7 hours

Question 48

In a class of 20 students, 12 like pizza and 8 like burgers. If you choose a student at random, what is the probability that they like burgers?

Accepted Answer

2/5

Answer

1/4

Answer

3/5

Answer

1/2

Question 49

A box has 5 red balls and 3 blue balls. You pick one ball, then another without putting the first one back. What is the probability of picking a red ball followed by a blue ball?

Accepted Answer

15/56

Answer

1/2

Answer

3/8

Answer

5/8

Question 50

A spinner has 8 equal sections numbered 1 to 8. What is the probability of spinning an even number?

Accepted Answer

1/2

Answer

1/8

Answer

3/4

Answer

1/4

Question 51

Five people are 15, 18, 21, 24, and 27 years old. What is the range of their ages?

Accepted Answer

12 years

Answer

24 years

Answer

18 years

Answer

21 years