Statistics and Probability Quiz

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

• Height of students in a class

• Temperature in a city

• Number of cars in a parking lot

• Time taken to run a marathon

Which of the following best describes a continuous random variable?

• Can take any value within a given range

• Has a finite number of possible values

• Can only take whole number values

• Is always an integer

What is a key difference between discrete and continuous random variables?

• Discrete: countable; Continuous: uncountable

• Discrete: positive; Continuous: negative

• Discrete: decimals; Continuous: whole numbers

• Discrete: time; Continuous: distance

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

• Number of students in a classroom

• Weight of a newborn baby

• Number of times a coin is flipped

• Whole number of books on a shelf

Apply your understanding to find the possible values of a discrete random variable representing the number of heads in three coin flips.

• 0, 1, 2, 3

• 0, 1, 2, 3, 4

• 1, 2, 3

• 1, 2, 3, 4

Apply your knowledge to illustrate a probability distribution for a discrete random variable representing the roll of a fair six-sided die. Which of the following is correct?

• Each outcome (1, 2, 3, 4, 5, 6) has a probability of 1/5

• Each outcome (1, 2, 3, 4, 5, 6) has a probability of 1/6

• Each outcome (1, 2, 3, 4, 5, 6) has a probability of 1/7

• Each outcome (1, 2, 3, 4, 5, 6) has a probability of 1/8

What is the formula for the mean (expected value) of a discrete random variable?

• (E(X) = \sum x P(x))

• (E(X) = \sum x^2 P(x))

• (E(X) = \sum P(x))

• (E(X) = \sum x)

Which of the following best describes a discrete random variable?

• Can take any value within a given range

• Has a finite number of possible values

• Can only take whole number values

• Is always an integer

What is the variance of a discrete random variable?

• Measure of central tendency

• Measure of frequency

• Measure of dispersion

• Measure of probability

How is the probability distribution of a discrete random variable represented?

• Bar graph

• Histogram

• Line graph

• Pie chart