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The following data is given, based on 450 students for marks in Statistics and Economics at a certain examination Mean marks in Statistics =40 Mean marks in Economics =48 S.D. of marks (Statistics) = 12 Variance of marks (Economics) =256 Sum of the products of deviations of marks from their respective mean = 42075. The average marks in Economics of candidates who obtained 50 marks in Statistics is (a) 45 (c)54 (b) 54.5
Answers (1)
Answer is 54.5. First find correlation coefficient which will come out to be 0.49. Based on this, find regression equation of Y (Marks in Economics) on X (Marks in Statistics). which will be Y = 0.65X +22. Substitute X = 50 and then calculate Y. Try this, if any doubt remains, feel free to mention here.