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Question
Choose the correct alternative.
Cov (x, y) = __________
Options
`sum (x - bar x)(y - bar y)`
`(sum (x - bar x)(y - bar y))/"n"`
`(sum xy)/"n" - bar x bar y`
both `(sum (x - bar x)(y - bar y))/"n"` and `(sum xy)/"n" - bar x bar y`
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Solution
Cov (x, y) = `underline ("both" (sum (x - bar x)(y - bar y))/"n" and (sum xy)/"n" - bar x bar y)`
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