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Let the mean and the standard deviation of the probability distribution array |c|c|c|c|c| X & & 1 & 0 & -3 P ( X ) & 1 3 & ~K & 1 6 & 1 4 array be and , respectively. If - =2 , then + is equal to________

Correct answer

0

Step-by-step solution

aligned & 1 3 + k + 1 6 + 1 4 =1 k = 1 4 & = 3 + 1 4 - 3 4 & = 3 - 1 2 & = ( ^2 1 3 + 1 4 +9 1 4 )- ( 3 - 1 2 )^2 & = 2 ^2 9 + 3 + 9 4 & = +2 & ^2=( +2)^2 2 ^2 9 + 3 + 9 4 = ^2 9 + 9 4 + & ^2 9 - 2 3 =0 & =0,( reject ) or =6 & ( x =0 is already given) & + =2 +2 & =5 aligned

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