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The mean and standard deviation of 20 ob...

The mean and standard deviation of 20 observations are found to be 10 and 2, respectively. On rechecking, it was found that an observation 8 was incorrect. Calculate the correct mean and standard deviation in each of the following cases:
(i) If wrong item is omitted. (ii) If it is replaced by 12.

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The correct Answer is:
`=1.989`
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NEW JOYTHI PUBLICATION-STATISTICS-QUESTIONS FROM COMPETITIVE EXAMS
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