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प्रश्न
For a bivariate data `barx = 10`, `bary = 12`, V(X) = 9, σy = 4 and r = 0.6
Estimate y when x = 5
Solution: Line of regression of Y on X is
`"Y" - bary = square ("X" - barx)`
∴ Y − 12 = `r.(σ_y)/(σ_x)("X" - 10)`
∴ Y − 12 = `0.6 xx 4/square ("X" - 10)`
∴ When x = 5
Y − 12 = `square(5 - 10)`
∴ Y − 12 = −4
∴ Y = `square`
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उत्तर
Solution: Line of regression of Y on X is
`"Y" - bary = bb(b_(yx)) ("X" - barx)`
∴ Y − 12 = `r.(σy)/(σx)("X" - 10)`
∴ Y − 12 = `0.6 xx (4/bb3) ("X" - 10)`
∴ When x = 5
Y − 12 = 0.8 (5 − 10)
∴ Y − 12 = −4
∴ Y = 8
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