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If sum(i=1)^(5) (x(i) - 6) = 5 and sum(i...

If `sum_(i=1)^(5) (x_(i) - 6) = 5` and `sum_(i=1)^(5)(x_(i)-6)^(2) = 25`, then the standard deviation of observations

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To find the standard deviation of the observations given the conditions, we will follow these steps: ### Step 1: Understand the Given Information We have two equations: 1. \(\sum_{i=1}^{5} (x_i - 6) = 5\) 2. \(\sum_{i=1}^{5} (x_i - 6)^2 = 25\) ### Step 2: Calculate the Mean of the Adjusted Values From the first equation, we can find the mean of the adjusted values \( (x_i - 6) \): \[ \text{Mean} = \frac{\sum_{i=1}^{5} (x_i - 6)}{5} = \frac{5}{5} = 1 \] ### Step 3: Calculate the Variance Variance is calculated using the formula: \[ \text{Variance} = \frac{\sum_{i=1}^{n} (x_i - a)^2}{n} - \left(\frac{\sum_{i=1}^{n} (x_i - a)}{n}\right)^2 \] Here, \( n = 5 \), \( a = 6 \). Using the second equation, we substitute: \[ \text{Variance} = \frac{25}{5} - \left(\frac{5}{5}\right)^2 \] Calculating this gives: \[ \text{Variance} = 5 - 1 = 4 \] ### Step 4: Calculate the Standard Deviation The standard deviation is the square root of the variance: \[ \text{Standard Deviation} = \sqrt{\text{Variance}} = \sqrt{4} = 2 \] ### Final Answer The standard deviation of the observations is \( 2 \). ---
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