Consider 15 observation and their mean was 8 and standard deviation was 3.But incorrect observation of 5 was considered . when the correct observation of 20 was taken , find new variance

The mean and variance of 20 observations are found to be 10 and 4. respectively. On rechecking, it was found that an observation 9 was incorrect and the correct observation was 11. Then the correct variance is

The standard deviation of 25 observations is 4 and their mean is 25. If each observation is increased by 10, what is the new variance-

For a group containing 100 observations, the arithmetic mean and standard deviation are 8 and sqrt(10.5) . For 50 observations selected from the 100 observations, the arithmetic mean and standard deviations are 10 and 2 respectively. Find the arithmetic mean and the standard deviation of the other half.

Variance of 3n observation is 4 , mean of first 2n observations is 6 and mean of next n observations is 3 . If 1 is added in first 2n observation and 1 is subtracted from last n observations than find new variance

The mean and variance of 10 observations are found to be 10 and 5 respectively. On rechecking it is found that an observation 5 is incorrect. If the incorrect observation is replaced by 15, then the correct variance is

The standard deviation of 25 observations is 4 and their mean is 25. If each observation is increased by 10, what is the new mean-

The mean of 5 observations is 4.4 and their variance is 8.24. If three of the observations are 1,2 and 6, find the other two observations.