The mean and standard deviation of 100 observations are 25 and 9 respectively. If 6 is subtracted from each observation, then mean and standard deviation will respectively be

The arithmetic mean of 100 observations is 50. If 10 is added to each observation then what will be the new arithmetic mean?

The sum of deviations of a set of observations x₁, x₂, ...., xₙ measured from 50 is −10 and the sum of deviations from 46 is 70, then the number of observations is

The mean and median of first 5 prime numbers are respectively M and Me. Then

If 131x + 217y = 827 and 217x + 131y = 913, then what are values of x and y respectively?

The median of the following distribution is 28.5, the values of x and y are respectively Class Interval: 0–10 | 10–20 | 20–30 | 30–40 | 40–50 | 50–60 Frequency: 5 | x | 20 | 15 | y | 5 where the tota…