Mean of x = 25 Mean of y = 20 σx = 4 σy = 3 r = 0.5 byx = □ bxy = □ when x = 10, y-□=□(10-□) ∴ y = □ - Mathematics and Statistics

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Mean of x = 25

Mean of y = 20

`sigma_x` = 4

`sigma_y` = 3

r = 0.5

byx = `square`

bxy = `square`

when x = 10,

`y - square = square (10 - square)`

∴ y = `square`

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Solution

Mean of x = 25

Mean of y = 20

`sigma_x` = 4

`sigma_y` = 3

r = 0.5

byx = `"r" sigma_y/sigma_x = 0.5 3/4` = 0.375

bxy = `"r" sigma_x/sigma_y = 0.5 4/3` = 0.667

when x = 10,

`y - bary = "b"_(yx)  (x - barx)`

`y - 20 = 0.375 (10 - 25)`

∴ y = 14.375

Concept: Properties of Regression Coefficients
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Chapter 2.3: Linear Regression - Q.5

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