Q. In the data set below, what is the variance?8,9,5,1,3,8,8If the answer is a decimal, round it to the nearest tenth.variance (σ2): _____
Calculate Sum of Squared Differences: Now, calculate the sum of the squared differences from the mean for each data point. Σ(xi−μ)2=(8−6)2+(9−6)2+(5−6)2+(1−6)2+(3−6)2+(8−6)2+(8−6)2=(2)2+(3)2+(−1)2+(−5)2+(−3)2+(2)2+(2)2=4+9+1+25+9+4+4=56
Find Variance: Finally, divide the sum of squared differences by the number of data points to find the variance.N=7 (number of data points)σ2=NΣ(xi−μ)2σ2=756σ2=8
Round to Nearest Tenth: Round the variance to the nearest tenth, if necessary. In this case, the variance is a whole number, so no rounding is needed.
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