Which of the following most likely represents a discrete random variable?
A) Length of time between calls to an 800 number.
B) The number of years completed in the military services.
C) The S & P Industrial average of stock prices.
D) The amount of retail sales on a given day.
E) Length of time for which an apartment in a large complex remains vacant.

Question

Quizplus · Accepted Answer

A discrete random variable is one that can take on a countable number of values. The length of time between calls to an 800 number (A) and the S & P Industrial average of stock prices (C) are continuous variables, meaning they can take on any value within a given range. The amount of retail sales on a given day (D) and the length of time for which an apartment in a large complex remains vacant (E) also have a continuous range of values. The number of years completed in the military services (B), on the other hand, can only take on discrete integer values (e.g. 1 year, 2 years, 3 years, etc.), making it the most likely choice for a discrete random variable.

Which of the Following Most Likely Represents a Discrete Random