Statistics · Mean and variance
The mean and variance of a data of 10 observations are 10 and 2, respectively. If an observation in this data is replaced by , then the mean and variance become 10.1 and 1.99, respectively. Then equals.
- (1)10
- (2)15
- (3)5
- (4)20
We corrected a printing error in the original paper
Source printed “If an observations ”.
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