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Question
For the two regression equations 4y = 9x + 15 and 25x = 6y + 7 find correlation coefficient r, `barx, bary`
Solution
Given equations of regression lines are
4y = 9x + 15 and 25x = 6y + 7
y = `9/4x + 15/4` and y = `25/6x - 7/6`
`9/4x + 15/4 and y = 25/6x - 7/6`
`|9/4| < |25/6|`
bxy = `9/4. 1/(b_xy) = 25/6`
bxy = `9/4. b_xy = 6/25`
r = `sqrt(b_xy xx b_yx)`
= `sqrt(6/25 xx 9/4)`
= `sqrt90.54)`
r = ± 0.7348
r = 0.7348 ............(bxy, byx > 0)
Solving equations of regressions lines
`barx = 118/46 . bary = 438/46`
Notes
Given equation of regression lines are
4y = 9x + 15 and 25x = 6y + 7
y = `9/4x + 15/4` and y = `25/6x -7/6`
`9/4x + 15/4`
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