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The mean and standard deviation of a gro...

The mean and standard deviation of a group of `100` observations were found to be `20` and `3`, respectively. Later on it was found that three observations were incorrect, which are recorded as `21, 21` and `18.` Find the mean and standard deviation if the incorrect observations are omitted.

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To find the new mean and standard deviation after omitting the incorrect observations, we can follow these steps: ### Step 1: Calculate the total sum of the original observations Given: - Mean (x̄) = 20 - Number of observations (n) = 100 The total sum of the observations (Σx) can be calculated as: ...
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