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The Mean Deviation for N Observations X 1 , X 2 , . . . , X N from Their Mean ¯ X is Given by

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Question

The mean deviation for n observations \[x_1 , x_2 , . . . , x_n\]  from their mean \[\bar{X} \]  is given by

 
  

Options

  •  \[\sum^n_{i = 1} \left( x_i - X \right)\]

  • \[\frac{1}{n} \sum^n_{i = 1} \left( x_i - X \right)\]

     
  •   \[\sum^n_{i = 1} \left( x_i - X \right)^2\]

  •   \[\frac{1}{n} \sum^n_{i = 1} \left( x_i - X \right)^2\]

MCQ
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Solution

The mean deviation for n observations \[x_1 , x_2 , . . . , x_n\]  from their mean \[\bar{ X } \]  is \[\frac{1}{n} \sum^n_{i = 1} \left| x_i - X \right|\]  . 

\[\frac{1}{n} \sum^n_{i = 1} \left| x_i - X \right|\]

 
 
 
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Chapter 32: Statistics - Exercise 32.9 [Page 52]

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R.D. Sharma Mathematics [English] Class 11
Chapter 32 Statistics
Exercise 32.9 | Q 23 | Page 52

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