Which of the following is not a discrete random variable?
A)The number of times a light changes red in a 10-minute cycle.
B)The number of minutes required to run 1 mile.
C)The number of defects in a sample selected from a population of 100 products.
D)The number of criminals found in a five-mile radius of a neighborhood.

Question

Quizplus · Accepted Answer

A and C are examples of discrete random variables because they have countable outcomes (the number of times a light changes, the number of defects). D could be considered discrete if we limit the radius to specific numbers (5 miles, 10 miles, etc.), but if the radius is continuous (e.g. all the way out to the edge of a city), it would be considered a continuous random variable. B, however, is not countable and has an infinite number of possible outcomes, making it a continuous random variable.

Which of the Following Is Not a Discrete Random Variable