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Maharashtra State BoardSSC (English Medium) 9th Standard

If x¯ is the mean of x1, x2 ............xn and y¯ is the mean of y1, y2, …….yn and z¯ is the mean of x1, x2 ............xn, y1, y2, ……….yn then z¯ =?

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Question

If `barx` is the mean of x1, x2 ............xn and `bary` is the mean of y1, y2, …….yn and `barz` is the mean of x1, x2 ............xn, y1, y2, ……….yn then `barz` =?

Options

  • `(bar x + bar y) / 2`

  • `bar x + bary`

  • `(bar x + bar y)/n`

  • ` (barx + bary)/(2n)`

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Solution

`bb((bar x + bar y) / 2)`

Explanation:

Z = `(nx + ny)/ (2n)`

= `[n ( bar x + bar y )] /( 2n)`

= `(bar x + bar y)/2`

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Chapter 7: Statistics - Problem Set 7 [Page 126]

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Balbharati Mathematics 1 [English] Standard 9 Maharashtra State Board
Chapter 7 Statistics
Problem Set 7 | Q (1) (v) | Page 126

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