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Question
A set of n values x1, x2, ..., xn has standard deviation 6. The standard deviation of n values x1 + k, x2 + k, ..., xn + k will be ______.
Options
σ
σ + k
σ – k
kσ
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Solution
A set of n values x1, x2, ..., xn has standard deviation 6. The standard deviation of n values x1 + k, x2 + k, ..., xn + k will be σ.
Explanation:
If each observation is increased by a constant k
Then standard deviation is unchanged.
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