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If the covariance between x and y is 30 , variance of x is 25 and variance of y is 144 , then what is the correlation coefficient?

Options

  1. A0.4
  2. B0.5
  3. C0.6
  4. D0.7

Correct answer

B. 0.5

Step-by-step solution

aligned & cov (x, y)=30 & var (x)=25 ; var (y)=144 & r(x, y)= cov (x, y) var (x) var (y) & r(x, y)= 30 25 144 = 30 5 12 =0.5 aligned

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