The mean of first three observations is 15 and the mean of next two observation is 20. The mean of all five observations is-

The mean of 5 observations is 60, the mean of 10 observations is 30 and the mean of 15 observations is 20. The mean of all the 30 observations is (a)20quad (b) 25quad (c) 30 (d) 40

If the mean of five observations is 11, find the mean of first three observations.

Mean of 35 observations is 75 .The mean of first 18 observations is 70 and the mean of last 18 observations is 80 .Then the 18^(th ) observation is

Mean of 35 observations is 75 .The mean of first 18 observations is 70 and the mean of last 18 observations is 80 .Then the 18^(" th ") observation is

The mean of first 8 observations is 18 and last 8 observations is 20. if the mean of all 15 observations is 19, find the 8th observations.

The mean of first three terms is 14 and mean of next two terms is 18. The mean of all the five terms is

The mean of first three terms is 14 and mean of next two terms is 18. The mean of all the five terms is

The mean of first three items is 14 and mean of next two items is 18. The mean of all the five terms is :

The mean of first three items is 14 and mean of next two items is 18. The mean of all the five terms is :