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प्रश्न
If `barx` is the mean of n values of x, then `sum_(i = 1)^n (x_i - barx)` is always equal to ______. If a has any value other than `barx`, then `sum_(i = 1)^n (x_i - barx)^2` is ______ than `sum(x_i - a)^2`
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उत्तर
If `barx` is the mean of n values of x, then `sum_(i = 1)^n (x_i - barx)` is always equal to 0. If a has any value other than `barx`, then `sum_(i = 1)^n (x_i - barx)^2` is less than `sum(x_i - a)^2`
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संबंधित प्रश्न
Find the mean deviation about the median for the data.
13, 17, 16, 14, 11, 13, 10, 16, 11, 18, 12, 17
Find the mean deviation about the median for the data.
36, 72, 46, 42, 60, 45, 53, 46, 51, 49
Find the mean deviation about the mean for the data.
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| 95 - 105 | 9 |
| 105 - 115 | 13 |
| 115 - 125 | 26 |
| 125 - 135 | 30 |
| 135 - 145 | 12 |
| 145 - 155 | 10 |
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| 0-10 | 6 |
| 10-20 | 8 |
| 20-30 | 14 |
| 30-40 | 16 |
| 40-50 | 4 |
| 50-60 | 2 |
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3011, 2780, 3020, 2354, 3541, 4150, 5000
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34, 66, 30, 38, 44, 50, 40, 60, 42, 51
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22, 24, 30, 27, 29, 31, 25, 28, 41, 42
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4, 7, 8, 9, 10, 12, 13, 17
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\[\bar{ X } \] + M.D, where M.D. is the mean deviation from the mean.
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\[\bar { X } \] − M.D. and
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\[\bar { X } \] − M.D. and
\[\bar { X } \] + M.D, where M.D. is the mean deviation from the mean.
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| No. of students | 5 | 8 | 15 | 16 | 6 |
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