Ungrouped data is the data you first gather from an experiment or study.
Example: It is easier to calculate the mean of a smaller set of numbers. When a larger set of data comes into the picture it becomes a tedious task to calculate the mean.
Consider the numbers 3,3,3,3,3,3,8,8,8,12,12. Though we can calculate this using our traditional method, it is time-consuming instead we can tabulate the data.
| x | 3 | 8 | 12 |
| f | 6 | 3 | 2 |
x = Depicts the values that this set will have
f = Frequency of each value.
It means 3 occurs 6 times, 8 occurs thrice and 12 occurs twice.
- Finding the mean
Sum of values = (3×6) + (8×3) + (12×2)
= 18+24+24 = 66
Number of values = 6+3+2 = 11
Mean = 66/11=66
- Formula
i = 1 to 3 as there are 3 terms (3,8,12)