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In the data set below, what is the variance?\newline2,9,6,8,8,4,52, 9, 6, 8, 8, 4, 5\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?\newline2,9,6,8,8,4,52, 9, 6, 8, 8, 4, 5\newlineIf the answer is a decimal, round it to the nearest tenth.\newlinevariance (σ2)(\sigma^2): _____
  1. Calculate Variance: Now, let's do the variance thing.\newlineWe need to sum up each (numbermean)2(\text{number} - \text{mean})^2.\newlineSo, (26)2+(96)2+(66)2+(86)2+(86)2+(46)2+(56)2(2 - 6)^2 + (9 - 6)^2 + (6 - 6)^2 + (8 - 6)^2 + (8 - 6)^2 + (4 - 6)^2 + (5 - 6)^2\newlineThat's (4)2+(3)2+(0)2+(2)2+(2)2+(2)2+(1)2(-4)^2 + (3)^2 + (0)^2 + (2)^2 + (2)^2 + (-2)^2 + (-1)^2\newlineWhich is 16+9+0+4+4+4+116 + 9 + 0 + 4 + 4 + 4 + 1\newlineSum = 3838
  2. Sum of Squares: Finally, divide that sum by the number of data points to get the variance.\newlineVariance=Sum7\text{Variance} = \frac{\text{Sum}}{7}\newlineVariance=387\text{Variance} = \frac{38}{7}\newlineVariance=5.428571\text{Variance} = 5.428571\ldots\newlineRound it to the nearest tenth and we get 5.45.4

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