Q. In the data set below, what is the variance?5,7,7,7,5,3,1If the answer is a decimal, round it to the nearest tenth.variance (σ2): _____
Calculate Squared Differences: Now that we have the mean, we calculate the squared differences from the mean for each data point.(5−5)2+(7−5)2+(7−5)2+(7−5)2+(5−5)2+(3−5)2+(1−5)2=02+22+22+22+02+(−2)2+(−4)2=0+4+4+4+0+4+16=32
Find Variance: Finally, we divide the sum of squared differences by the number of data points to find the variance.Number of data points N=7Variance σ2=NΣ(xi−μ)2σ2=732σ2≈4.57142857143Rounded to the nearest tenth: σ2≈4.6
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