how to find the mean of a frequency table
how to find the mean of a frequency table
To find the mean of a frequency table, you need to follow these steps:
- Create a frequency table for the data set. A frequency table shows how many times each value in the data set occurs.
- Add a column for the product of each data point and its frequency. In other words, multiply each data point by the number of times it occurs in the data set.
- Add up the values in the product column.
- Add up the frequencies in the frequency column.
- Divide the total value in the product column by the total frequency to get the mean.
Here’s an example of how to use these steps:
Suppose you have the following frequency table for a data set:
| Data value | Frequency |
|---|---|
| 10 | 3 |
| 20 | 6 |
| 30 | 2 |
| 40 | 4 |
To find the mean of this data set, you would first add a column for the product of each data point and its frequency:
| Data value | Frequency | Product |
|---|---|---|
| 10 | 3 | 30 |
| 20 | 6 | 120 |
| 30 | 2 | 60 |
| 40 | 4 | 160 |
Next, you would add up the values in the product column and the frequencies column:
Total product = 30 + 120 + 60 + 160 = 370
Total frequency = 3 + 6 + 2 + 4 = 15
Finally, you would divide the total product by the total frequency to get the mean:
Mean = Total product / Total frequency = 370 / 15 = 24.67
Therefore, the mean of this data set is 24.67.