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Mean of x = 25
Mean of y = 20
`sigma_x` = 4
`sigma_y` = 3
r = 0.5
b_{yx} = `square`
b_{xy} = `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
b_{yx} = `"r" sigma_y/sigma_x = 0.5 3/4` = 0.375
b_{xy} = `"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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