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Question
If the S.D. of a set of observations is 8 and if each observation is divided by −2, the S.D. of the new set of observations will be
Options
−4
−8
8
4
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Solution
4
\[\text{ New} S . D . = \left| - \frac{1}{2} \right| \times 8\]
\[ = \frac{8}{2}\]
\[ = 4\]
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