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Question
For a bivariate data,
`bar x = 53 , bar y = 28 , "b"_"xy" = - 0.2` , `"b"_"yx" = -1.5` Find
Estimate of Y , When X = 50.
Solution
Equation of regression of y on x is
`"Y" - bar y = "b"_"yx" ("X" - bar x)`
Y - 28 = - 1.5 (X - 53)
Y = - 1.5 X + 79.5 + 28
when X = 50 ,
Y = - 1.5 (50) + 107.5
Y = - 75 + 107.5
Y = 32.5
∴ Estimate of Y when X = 50 is 32.5
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