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If r is the coefficient of correlation between x and y , then what is the correlation coefficient between (3 x+4) and (-3 y+3) ?

Options

  1. A-r
  2. Br
  3. C3 r
  4. D- 3 r

Correct answer

A. -r

Step-by-step solution

aligned & r= cor (x, y) var (x) var (y) & cor (3 x 4,-3 y+3)= (3 x-3 x^ ) (-3 y+3 y^ ) & =-9 cor (x, y) & r(3 x+4,-3 y+3)= -9 cor (x, y) 9 cor (x)- 9 var (y) & = -9 cor (x, y) 9 var (x) var (y) =-r aligned

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