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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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