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The coefficient of correlation between ages of husband and wife at the time of marriage for a given set of 100 couples was noted to be 0 7 . Assume that all these couples survive to celebrate the silver jubilee of their marriage. The coefficient of correlation at that point of time will be

Options

  1. A1
  2. B0.9
  3. C0.7
  4. D0.3

Correct answer

C. 0.7

Step-by-step solution

r= (x_i- x ) (y_i- y ) (x_i- x )^2 (y_i- y )^2 =0.7 At time of silver jubilee new x and y increase 25 also each x i and y i increase with 25 Therefore, (x i- x ),(y i- y ) not change So, coefficient of correlation remains same Hence, new coefficient of correlation =0.7

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