Q. In the data set below, what is the variance?9,5,5,2,2,5,7If the answer is a decimal, round it to the nearest tenth.variance (σ2): _____
Calculate Mean: Calculate the mean of the data set.Mean = (9+5+5+2+2+5+7)/7μ=35/7μ=5
Calculate Squared Differences: Data set: 9,5,5,2,2,5,7 μ=5 Calculate the sum of the squared differences from the mean. (9−5)2+(5−5)2+(5−5)2+(2−5)2+(2−5)2+(5−5)2+(7−5)2 =(4)2+(0)2+(0)2+(−3)2+(−3)2+(0)2+(2)2 =16+0+0+9+9+0+4 =38
Calculate Variance: We know:Σ(xi−μ)2=38N=7Calculate the variance and round your answer to the nearest tenth.σ2=(Σ(xi−μ)2)/Nσ2=38/7σ2≈5.4 (rounded to the nearest tenth)
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