Question:medium
If \( \sum_{i=1}^{10} (x_i + 2)^2 = 180 \) and \( \sumᵢ=1¹0 (xᵢ - 1)² = 90 , then the Standard Deviation is equal to
If \( \sum_{i=1}^{10} (x_i + 2)^2 = 180 \) and \( \sumᵢ=1¹0 (xᵢ - 1)² = 90 , then the Standard Deviation is equal to
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When expressions like \((x_i+a)^2\) or \((x_i-a)^2\) are given, expand them to form equations in \(\sum x_i\) and \(\sum x_i^2\).
Updated On: Apr 6, 2026
- \(3\)
- \(2\)
- \(4\)
- \(5\)
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The Correct Option is A
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