Q. In the data set below, what is the variance?4,4,4,9,7,3,4If the answer is a decimal, round it to the nearest tenth.variance (σ2): _____
Calculate Mean: Calculate the mean of the data set.Mean = (4+4+4+9+7+3+4)/7μ=35/7μ=5
Calculate Sum of Squared Differences: Data set: 4,4,4,9,7,3,4 μ=5 Calculate the sum of the squared differences from the mean, Σ(xi−μ)2. (4−5)2+(4−5)2+(4−5)2+(9−5)2+(7−5)2+(3−5)2+(4−5)2 =(−1)2+(−1)2+(−1)2+(4)2+(2)2+(−2)2+(−1)2 =1+1+1+16+4+4+1 =28
Calculate Variance: We know:Σ(xi−μ)2=28N=7Calculate the variance and round your answer to the nearest tenth.σ2=(Σ(xi−μ)2)/Nσ2=28/7σ2=4Since the result is not a decimal, there is no need to round.
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