Question:
The mean square deviation of a set of n observations about points -2 and 2 are 18 and 10 respectively. The standard deviation of the set is
The mean square deviation of a set of n observations about points -2 and 2 are 18 and 10 respectively. The standard deviation of the set is
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Mean square deviation = variance + square of shift.
Updated On: Mar 20, 2026
- \(3\)
- \(2\)
- \(1\)
- None of these
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The Correct Option is A
Solution and Explanation
Let mean =μ, variance =σ².
σ²+(μ+2)²=18, σ²+(μ-2)²=10
Subtracting,
8μ=8⟹ μ=1
σ²=10-(1-2)²=9⟹ σ=3
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