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Question
The regression equation of y on x is 2x – 5y + 60 = 0
Mean of x = 18
`2 square - 5 bary + 60` = 0
∴ `bary = square`
`sigma_x : sigma_y` = 3 : 2
∴ byx = `square/square`
∴ byx = `square/square`
∴ r = `square`
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Solution
The regression equation of y on x is 2x – 5y + 60 = 0.
Mean of x = 18
`2barx - 5bary + 60` = 0
`2 xx 8 - 5bary + 60` = 0
∴ `5 bary` = 36 + 60
∴ `5 bary` = 96
∴ `bary` = 19.2
`sigma_x : sigma_y` = 3 : 2
2x – 5y + 60 = 0 ⇒ y = 0.4x + 12
∴ byx = `2/5`
∴ byx = `("r"sigma_y)/sigma_`
∴ 0.4 = `"r"xx 2/3`
∴ r = `0.4 xx 3/2`
∴ r = 0.6
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