Questions: Consider the following data:
10, 15, 9, 12, 14, 6
Step 1 of 3: Calculate the value of the sample variance. Round your answer to one decimal place.
Transcript text: Consider the following data:
\[
10,15,9,12,14,6
\]
Step 1 of 3: Calculate the value of the sample variance. Round your answer to one decimal place.
Answer
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Solution
Solution Steps
Step 1: Calculate the sample mean
The sample mean \(\bar{x}\) is calculated as \(\bar{x} = \frac{\sum_{i=1}^{n} x_i}{n}\), where \(n\) is the total number of data points. For our dataset, this is \(\bar{x} = 11\).
Step 2: Calculate the deviations from the mean for each data point
For each data point \(x_i\), we calculate the deviation from the mean as \(x_i - \bar{{x}}\).
Step 3: Square each deviation
Each deviation from the mean is squared to ensure positive and negative deviations do not cancel each other out: \((x_i - \bar{{x}})^2\).
Step 4: Sum all squared deviations
All squared deviations are summed: \(\sum_{{i=1}}^{{n}} (x_i - \bar{{x}})^2\).
Step 5: Divide by \(n-1\)
The sum of squared deviations is divided by \(n-1\) to find the sample variance: \(s^2 = \frac{\sum_{i=1}^{n} (x_i - \bar{x})^2}{n-1}\), which gives us \(s^2 = 11.2\).
Final Answer:
The sample variance of the given dataset, rounded to 1 decimal places, is 11.2.