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In the data set below, what is the variance?\newline9,4,9,4,6,19, 4, 9, 4, 6, 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?\newline9,4,9,4,6,19, 4, 9, 4, 6, 1\newlineIf the answer is a decimal, round it to the nearest tenth.\newlinevariance (σ2)(\sigma^2): _____
  1. Calculate squared differences: Now, calculate the squared differences from the mean for each data point.\newline(95.5)2+(45.5)2+(95.5)2+(45.5)2+(65.5)2+(15.5)2(9 - 5.5)^2 + (4 - 5.5)^2 + (9 - 5.5)^2 + (4 - 5.5)^2 + (6 - 5.5)^2 + (1 - 5.5)^2\newline= (3.5)2+(1.5)2+(3.5)2+(1.5)2+(0.5)2+(4.5)2(3.5)^2 + (-1.5)^2 + (3.5)^2 + (-1.5)^2 + (0.5)^2 + (-4.5)^2\newline= 12.25+2.25+12.25+2.25+0.25+20.2512.25 + 2.25 + 12.25 + 2.25 + 0.25 + 20.25\newline= 49.549.5
  2. Find the variance: Finally, divide the sum of squared differences by the number of data points to find the variance.\newlineσ2=Σ(xiμ)2N\sigma^2 = \frac{\Sigma(x_i - \mu)^2}{N}\newlineσ2=49.56\sigma^2 = \frac{49.5}{6}\newlineσ2=8.25\sigma^2 = 8.25\newlineSince we need to round to the nearest tenth, σ28.3\sigma^2 \approx 8.3

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