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AP EAMCET202315 May 2023Evening ShiftMathematicsStatisticsActual

The mean of 5 observations is 4.4 and their variance is 8.24. If three of those observations are 1,2 and 6 , then the other two observations are

Options

  1. A9,4
  2. B9,5
  3. C9,2
  4. D9,13

Correct answer

A. 9,4

Step-by-step solution

Let other two observation be x and y4.4= 1+2+6+x+y 5 x+y=13...(i) and 8.24= 1 5 (1^2+2^2+6^2+x^2+y^2 )-(4.4)^2 x^2+y^2=97 Now, x^2+y^2= (x+y)^2+(x-y)^2 2 2 97-13^2=(x-y)^2 (x-y)=5...(ii) On solving (i) & (ii) we get, x=9 and y=4

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