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Question
Find the mean of the following distribution:
| x | 4 | 6 | 9 | 10 | 15 |
| f | 5 | 10 | 10 | 7 | 8 |
Solution
Calculation of Arithmetic MEan:
| `x_i` | `f_i` | `f_ix_i` |
| 4 | 5 | 20 |
| 6 | 10 | 60 |
| 9 | 10 | 90 |
| 10 | 7 | 70 |
| 15 | 8 | 120 |
| N = `sumf_i` = 40 | `sumf_ix_i` = 360 |
∴ Mean = `bar"X" = (sumf_ix_i)/(sumf_i) = (360)/(40)` = 9.
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