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Find the mean deviation about the mean of the distribution: Size 20 21 22 23 24 Frequency 6 4 5 1 4

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प्रश्न

Find the mean deviation about the mean of the distribution:

Size 20 21 22 23 24
Frequency 6 4 5 1 4
सारिणी
योग
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उत्तर

Size `(x_i)` Frequency `(f_i)` `f_ix_i` `d_i = |x_i - barx_i|` `f_i d_i`
20 6 120 1.65 9.90
21 4 84 0.65 2.60
22 5 110 0.35 1.75
23 1 23 1.35 1.35
24 4 96 2.35 9.40
Total 20 433 6.35 25.00

Mean `barx = (sumf_ix_i)/(sumf_i)`

= `433/20`

= 21.65

Mean deviation MD = `(sumf_i d_i)/(sumf_i)`

= `25/20`

= 1.25

Here, the required MD = 1.25

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अध्याय 15: Statistics - Exercise [पृष्ठ २७८]

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एनसीईआरटी एक्झांप्लर Mathematics Exemplar [English] Class 11
अध्याय 15 Statistics
Exercise | Q 1 | पृष्ठ २७८

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