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Question
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`
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
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