You can calculate the mean of a frequency table by using the following formula:
Mean = Σfx / Σf
where:
- Σ: A fancy symbol that means “sum”
- f: The frequency of a particular value
- x: The value in the frequency table
The following examples show how to use this formula in practice.
Example 1: Mean Number of Wins
The following frequency table shows the total number of wins for 30 soccer teams in a certain league:
We can use the following formula to calculate the mean number of wins:
- Mean = (0*2 + 1*3 + 2*7 + 3*8 + 4*7 + 5*3) / (2 + 3 + 7 + 8 + 7 + 3)
- Mean = (0 + 3 + 14 + 24 + 28 + 15) / (30)
- Mean = (84) / (30)
- Mean = 2.8
The mean number of wins is 2.8.
Example 2: Mean Number of Pets
The following frequency table shows the total number of pets owned by 20 different families in a certain neighborhood:
We can use the following formula to calculate the mean number of pets owned:
- Mean = (0*2 + 1*10 + 2*4 + 3*3 + 4*1) / (2 + 10 + 4 + 3 + 1)
- Mean = (0 + 10 + 8 + 9 + 4) / (20)
- Mean = (31) / (20)
- Mean = 1.55
The mean number of pets owned is 1.55.
Example 3: Mean Household Size
The following frequency table shows the household size of 40 different households in a particular area:
We can use the following formula to calculate the mean household size:
- Mean = (1*2 + 2*4 + 3*14 + 4*13 + 5*4 + 6*2 + 7*1) / (2 + 4 + 14 + 13 + 4 + 2+1)
- Mean = (2 + 8 + 42 + 52 + 20 + 12 + 7) / (40)
- Mean = (143) / (40)
- Mean = 3.575
The mean household size is 3.575.
Additional Resources
How to Calculate Median from Frequency Table
How to Calculate Mode from Frequency Table
How to Find Mean, Median, & Mode in Stem-and-Leaf Plots
How to Estimate the Mean and Median of Histograms
When to Use Mean vs. Median