Q. In the data set below, what is the variance?1,5,7,3,8If the answer is a decimal, round it to the nearest tenth.variance σ2: _____
Subtract and Square: Now, subtract the mean from each data point and square the result to find the squared differences.(1−4.8)2=(−3.8)2=14.44(5−4.8)2=(0.2)2=0.04(7−4.8)2=(2.2)2=4.84(3−4.8)2=(−1.8)2=3.24(8−4.8)2=(3.2)2=10.24
Sum Squared Differences: Sum the squared differences to find the total squared variation from the mean.Σ(xi−μ)2=14.44+0.04+4.84+3.24+10.24Σ(xi−μ)2=32.8
Calculate Variance: Divide the total squared variation by the number of data points (N) to find the variance.N=5 (since there are 5 data points)σ2=NΣ(xi−μ)2σ2=532.8σ2=6.56
Round to Nearest Tenth: Round the variance to the nearest tenth. σ2≈6.6
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