The regression equation of y on x is 2x – 5y + 60 = 0 Mean of x = 18 2□- 5 y¯+60 = 0 ∴ y¯=□ σx:σy = 3 : 2 ∴ byx = □□ ∴ byx = □□ ∴ r = □ - Mathematics and Statistics

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Sum

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

Concept: Properties of Regression Coefficients
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Chapter 2.3: Linear Regression - Q.5

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