What is the mode of the data set 1, 2, 3, 4, 5?

• A. 2
• B. 3
• C. 4
• D. No mode

Answer: (D)

Mode is the value that occurs most often. In this set, every number from 1 through 5 appears exactly once, so no value appears more frequently than another. Because there isn’t a single most frequent value, there is no mode. If something were repeated, that repeated value would be the mode; if several values tied for the highest frequency, there would be multiple modes. Here, since all frequencies are equal, the standard conclusion is no mode.