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Question
Find the mean deviation from the mean for the data:
| xi | 5 | 10 | 15 | 20 | 25 |
| fi | 7 | 4 | 6 | 3 | 5 |
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Solution
| xi | fi | fixi |
\[\left| x_i - \bar{x} \right|\]
|
\[f_i \left| x_i - 14 \right|\]
|
| 5 | 7 | 35 | 9 | 63 |
| 10 | 4 | 40 | 4 | 16 |
| 15 | 6 | 90 | 1 | 6 |
| 20 | 3 | 60 | 6 | 18 |
| 25 | 5 | 125 | 11 | 55 |
|
\[N = 25\]
|
\[\sum^n_{i = 1} f_i x_i = 350\]
|
\[\sum^n_{i = 1} f_i \left| x_i - 14 \right| = 158\]
|
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| xi | 5 | 10 | 15 | 20 | 25 |
| fi | 7 | 4 | 6 | 3 | 5 |
