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If barx represents the mean of n observa...

If `barx` represents the mean of n observations `x_(1), x_(2),………., x_(n)`, then values of `Sigma_(i=1)^(n) (x_(i)-barx)`

A

`-1`

B

0

C

1

D

`n-1`

Text Solution

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The correct Answer is:
To solve the question, we need to evaluate the expression \( \Sigma_{i=1}^{n} (x_{i} - \bar{x}) \), where \( \bar{x} \) is the mean of the observations \( x_{1}, x_{2}, \ldots, x_{n} \). ### Step-by-Step Solution: 1. **Understanding the Mean**: The mean \( \bar{x} \) of the observations \( x_{1}, x_{2}, \ldots, x_{n} \) is defined as: \[ \bar{x} = \frac{\Sigma_{i=1}^{n} x_{i}}{n} \] 2. **Substituting the Mean into the Summation**: We want to evaluate: \[ \Sigma_{i=1}^{n} (x_{i} - \bar{x}) \] We can rewrite this as: \[ \Sigma_{i=1}^{n} x_{i} - \Sigma_{i=1}^{n} \bar{x} \] 3. **Calculating Each Part**: - The first part \( \Sigma_{i=1}^{n} x_{i} \) is simply the sum of all observations. - The second part \( \Sigma_{i=1}^{n} \bar{x} \) can be simplified. Since \( \bar{x} \) is a constant (the mean), we have: \[ \Sigma_{i=1}^{n} \bar{x} = n \cdot \bar{x} \] 4. **Substituting Back**: Now substituting these back into our expression, we get: \[ \Sigma_{i=1}^{n} (x_{i} - \bar{x}) = \Sigma_{i=1}^{n} x_{i} - n \cdot \bar{x} \] 5. **Using the Definition of Mean**: From the definition of the mean, we know that: \[ n \cdot \bar{x} = \Sigma_{i=1}^{n} x_{i} \] Therefore, we can substitute this into our expression: \[ \Sigma_{i=1}^{n} (x_{i} - \bar{x}) = \Sigma_{i=1}^{n} x_{i} - \Sigma_{i=1}^{n} x_{i} = 0 \] 6. **Conclusion**: Thus, the value of \( \Sigma_{i=1}^{n} (x_{i} - \bar{x}) \) is: \[ 0 \] ### Final Answer: The value of \( \Sigma_{i=1}^{n} (x_{i} - \bar{x}) \) is **0**.

To solve the question, we need to evaluate the expression \( \Sigma_{i=1}^{n} (x_{i} - \bar{x}) \), where \( \bar{x} \) is the mean of the observations \( x_{1}, x_{2}, \ldots, x_{n} \). ### Step-by-Step Solution: 1. **Understanding the Mean**: The mean \( \bar{x} \) of the observations \( x_{1}, x_{2}, \ldots, x_{n} \) is defined as: \[ \bar{x} = \frac{\Sigma_{i=1}^{n} x_{i}}{n} ...
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