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प्रश्न
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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उत्तर
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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Mean of x = 53
Mean of y = 28
Regression coefficient of y on x = – 1.2
Regression coefficient of x on y = – 0.3
a. r = `square`
b. When x = 50,
`y - square = square (50 - square)`
∴ y = `square`
c. When y = 25,
`x - square = square (25 - square)`
∴ x = `square`
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Mean of x = 18
`2 square - 5 bary + 60` = 0
∴ `bary = square`
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∴ byx = `square/square`
∴ byx = `square/square`
∴ r = `square`
If byx > 1 then bxy is _______.
