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AP EAMCET202017 Sep 2020Morning ShiftMathematicsStatisticsActual

If the standard deviation of the numbers 2,3 , (2 x ) and 11 is 3.5. Find the possible values of (x ).

Options

  1. A(2 7 2 )
  2. B(3 5 3 )
  3. C(2 5 2 )
  4. D(3 7 3 )

Correct answer

D. (3 7 3 )

Step-by-step solution

( =3.5 ) ( gathered Mean ( x )= 2+3+2 x+11 4 = (4+ x 2 ) ^2= 1 n (x_i- x )^2 (3 5)^2= 1 4 [ (-2- x 2 )^2+ (-1- x 2 )^2+ ( 3 x 2 -4 )^2+ (7- x 2 )^2 ] 3 x^2-16 x+21=0 x= 7 3 , 3 gathered )

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