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प्रश्न
For certain bivariate data on 5 pairs of observations given:
∑x = 20, ∑y = 20, ∑x2 = 90, ∑y2 = 90, ∑xy = 76 then bxy = ______.
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उत्तर
∑x = 20, ∑y = 20, ∑x2 = 90, ∑y2 = 90, ∑xy = 76 then bxy = – 0.4.
Explanation:
`barx = (sumx)/n = 20/5` = 4
`bary = (sumy)/n = 20/5` = 4
bxy = `(sumxy - n.barx.bary)/(sumy^2 - n.bary^2)`
= `(76 - 5 xx 4 xx 4)/(90 - 5 xx 4^2)`
= `(76 - 80)/(90 - 80)`
= `(-4)/10`
= – 0.4
bxy = – 0.4
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