If the three observations are 3, -6 and -6, then what is their harmonic mean?

The mean of five observations is 4 and their variance is 5.2. If three of these observations are 2, 4 and 6, then the other two observations are :

The mean of five observations is 4 and their variance is 5.2. If three of these observations are 2, 4 and 6, then the other two observations are :

The mean of five observations is 4 and their variance is 5.2. If three of these observations are 2, 4 and 6, then the other two observations are

The means of five observations is 4 and their variance is 5.2. If three of these observations are 1,2 and 6, then the other two are 2 and 9 (b) 3 and 8 4 and 7 (d) 5 and 6

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

The means of five observations is 4 and their variance is 5.2. If three of these observations are 1,2 and 6, then the other two are (a) 2 and 9 , (b) 3 and 8 , (c) 4 and 7 , (d) 5 and 6