If u = x-ac and v = y-bd, then bxy = ______ - Mathematics and Statistics

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If u = `(x - "a")/"c"` and v = `(y - "b")/"d"`, then bxy = ______ 

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Solution

`"c"/"d"` buv 

Concept: Properties of Regression Coefficients
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Chapter 2.3: Linear Regression - Q.3

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x y xy x2 y2
6 9 54 36 81
2 11 22 4 121
10 5 50 100 25
4 8 32 16 64
8 7 `square` 64 49
Total = 30 Total = 40 Total = `square` Total = 220 Total = `square`

bxy = `square/square`

byx = `square/square`

∴ Regression equation of x on y is `square`

∴ Regression equation of y on x is `square`


bxy . byx = ______.


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