Q. In the data set below, what is the variance?1,9,9,9,7,4,3If the answer is a decimal, round it to the nearest tenth.variance (σ2): _____
Calculate Mean: Calculate the mean of the data set.Mean = (1+9+9+9+7+4+3)/7μ=42/7μ=6
Calculate Sum of Squared Differences: Data set: 1,9,9,9,7,4,3 μ=6 Calculate the sum of the squared differences from the mean. (1−6)2+(9−6)2+(9−6)2+(9−6)2+(7−6)2+(4−6)2+(3−6)2 =(−5)2+(3)2+(3)2+(3)2+(1)2+(−2)2+(−3)2 =25+9+9+9+1+4+9 =66
Calculate Variance: We have:Σ(xi−μ)2=66N=7Calculate the variance and round your answer to the nearest tenth.σ2=NΣ(xi−μ)2σ2=766σ2≈9.4 when rounded to the nearest tenth.
More problems from Variance and standard deviation