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For a bivariate date, you are given foll...

For a bivariate date, you are given following information:
` sum x = 125 , sum x^(2) = 1650 , sum y = 100 , sum y^(2) = 1500 , sum xy= 50 , n= 25`
Find line of regression.

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To find the line of regression for the given bivariate data, we will use the formulas for the coefficients \( a \) and \( b \) in the regression equation \( y = a + bx \). ### Step 1: Identify the given values We are given: - \( \Sigma x = 125 \) - \( \Sigma x^2 = 1650 \) - \( \Sigma y = 100 \) - \( \Sigma y^2 = 1500 \) - \( \Sigma xy = 50 \) - \( n = 25 \) ### Step 2: Calculate the slope \( b \) The formula for \( b \) is: \[ b = \frac{n \Sigma xy - \Sigma x \Sigma y}{n \Sigma x^2 - (\Sigma x)^2} \] Substituting the given values: \[ b = \frac{25 \cdot 50 - 125 \cdot 100}{25 \cdot 1650 - (125)^2} \] Calculating the numerator: \[ 25 \cdot 50 = 1250 \] \[ 125 \cdot 100 = 12500 \] Thus, \[ n \Sigma xy - \Sigma x \Sigma y = 1250 - 12500 = -11250 \] Calculating the denominator: \[ 25 \cdot 1650 = 41250 \] \[ (125)^2 = 15625 \] Thus, \[ n \Sigma x^2 - (\Sigma x)^2 = 41250 - 15625 = 25625 \] Now substituting back into the formula for \( b \): \[ b = \frac{-11250}{25625} \approx -0.439 \] ### Step 3: Calculate the intercept \( a \) The formula for \( a \) is: \[ a = \frac{\Sigma y \Sigma x^2 - \Sigma x \Sigma xy}{n \Sigma x^2 - (\Sigma x)^2} \] Substituting the values: \[ a = \frac{100 \cdot 1650 - 125 \cdot 50}{25 \cdot 1650 - (125)^2} \] Calculating the numerator: \[ 100 \cdot 1650 = 165000 \] \[ 125 \cdot 50 = 6250 \] Thus, \[ \Sigma y \Sigma x^2 - \Sigma x \Sigma xy = 165000 - 6250 = 158750 \] Now substituting back into the formula for \( a \): \[ a = \frac{158750}{25625} \approx 6.194 \] ### Step 4: Write the regression equation Now that we have \( a \) and \( b \), we can write the equation of the regression line: \[ y = a + bx \] Substituting the values of \( a \) and \( b \): \[ y = 6.194 - 0.439x \] ### Final Answer The equation of the regression line is: \[ y = 6.194 - 0.439x \]
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