Two series A and B with equal means standard deviation 9 and 10 respectively . Which series is more consistent ?

The coefficient of variation of two series are 70 and 90 and their standard deviation are 17.5 and 18 respectively.The mean of two series are

For a group of 100 observations, the arithmetic mean and standard deviation are 8 and sqrt(10.5) respectively. The mean and standard deviation of 50 items selected from these 100 observations are 10 and 2 respectively. Then the standard deviation of the remaining 50 observation is

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.

The mean and standard deviation for a,b and 2 are 3 and 1 respectively,then value of ab is

Find out standard deviation and its coefficient of the following series:

Two sample of size 100 and 150 respectively have means 15 and 16 and standard deviations 3 and 4 respectively. Find the combined mean and standard deviation of Size 250.

The mean and standard deviation of two numbers are 10 and 2 respectively. Find the numbers.

The mean of 100 observations is 40 and their standard deviation respectively is 10. if 5 is added to each observation then the new mean and new standard deviation will be

Find the standard deviation of the following discrete series .