The mean is the mathematical average. The median is the middle value. The mode is the most repeated value. The range is the difference between the greatest and least value.
Mean: 12.1 Median: 12 Mode: 12 Range: 2
Practice makes perfect
We want to find the mean, median, mode, and range of the following data set.
12, 12, 13, 12, 12, 12, 12, 12, 12, 13, 12, 11, 12, 12, 12, 12, 12
Mean
The mean of a data set is the sum of the values divided by the total number of values in the set. Let's start by calculating the sum of the given values.
12+12+13+12+12+12+12
12+12+13+12+11+12+12
+12+12+12
= 205
There are 17 values in our set, so we have to divide the sum by 17.
Mean: 205/17=12.058824...
We can approximate the mean to the nearest tenth.
Mean: 205/17≈ 12.1
Median
When the data are arranged in numerical order, the median is the middle value — or the mean of the two middle values — in a set of data. Let's arrange the given values and find the median.
11, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 13, 13
The median of this set is 12.
Mode
The mode is the value or values that appear most often in a set of data.
Let's find the mode of the given values.
11, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 13, 13
The value that appears most often is 12.
Mode: 12
Range
The range is the difference between the greatest and least values in a set of data.
11, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 13, 13
For our exercise, the greatest value is 13 and the least value is 11.
Range: 13-11=2
