Chapter 5 - Discrete Probability Distributions - 5-2 Mean, Variance, Standard Deviation, and Expectation - Exercises 5-2 - Page 272: 7

Mean = μ = ∑X * P(X) = (1*1/9)+(2*1/9)+(3*1/9)+(4*1/9)+(5*1/9)+(6*1/9)+(7*1/9)+(8*1/9)+(9*1/9) = 5 Variance = $ σ ^{2}$ = ∑[$X ^{2}$ * P(X)] - $ μ ^{2}$ =[ $1 ^{2}$ *1/9 +$2 ^{2}$ *1/9 + $3 ^{2}$ *1/9 + $4 ^{2}$ *1/9 + $5 ^{2}$ *1/9+ $6 ^{2}$ *1/9+ $7 ^{2}$ *1/9+ $8 ^{2}$ *1/9+ $9 ^{2}$ *1/9 ] -$ 5 ^{2}$ =31.66667-25 =6.66667 Standard Deviation = σ = $ \sqrt σ ^{2}$ = $\sqrt 6.66667$ = 2.582

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