Numerical Measures of Central Tendency and Variability

Read these sections and complete the questions at the end of each section. First, we will define central tendency and introduce mean, median, and mode. We will then elaborate on median and mean and discusses their strengths and weaknesses in measuring central tendency. Finally, we'll address variability, range, interquartile range, variance, and the standard deviation. 

Measures of Central Tendency


  1. (2+4+6+8) / 4=5

  2. 3
    Because there are 5 numbers, the median is the middle number when they are ranked from lowest to highest.

  3. What is the mode of -2, 4, 0, 3, 0, 2, 4, 4, and 8?

  4. Mean = 85, Median = 84, Mode = 75, so the mean of his scores is the highest.

  5. If the teacher is going to use the median as the final grade, she should only argue the middle score (87). Changing the other scores by 2 points would not affect the median.