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In the data set below, what is the variance?\newline5,7,7,7,5,3,15, 7, 7, 7, 5, 3, 1\newlineIf the answer is a decimal, round it to the nearest tenth.\newlinevariance (σ2)(\sigma^2): _____

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Q. In the data set below, what is the variance?\newline5,7,7,7,5,3,15, 7, 7, 7, 5, 3, 1\newlineIf the answer is a decimal, round it to the nearest tenth.\newlinevariance (σ2)(\sigma^2): _____
  1. Calculate Squared Differences: Now that we have the mean, we calculate the squared differences from the mean for each data point.\newline(55)2+(75)2+(75)2+(75)2+(55)2+(35)2+(15)2(5 - 5)^2 + (7 - 5)^2 + (7 - 5)^2 + (7 - 5)^2 + (5 - 5)^2 + (3 - 5)^2 + (1 - 5)^2\newline=02+22+22+22+02+(2)2+(4)2= 0^2 + 2^2 + 2^2 + 2^2 + 0^2 + (-2)^2 + (-4)^2\newline=0+4+4+4+0+4+16= 0 + 4 + 4 + 4 + 0 + 4 + 16\newline=32= 32
  2. Find Variance: Finally, we divide the sum of squared differences by the number of data points to find the variance.\newlineNumber of data points N=7N = 7\newlineVariance σ2=Σ(xiμ)2N\sigma^2 = \frac{\Sigma(x_i - \mu)^2}{N}\newlineσ2=327\sigma^2 = \frac{32}{7}\newlineσ24.57142857143\sigma^2 \approx 4.57142857143\newlineRounded to the nearest tenth: σ24.6\sigma^2 \approx 4.6

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