Practice Questions: Statistics

Try yourself: If the mean of five observations x, x + 2, x + 4, x + 6 and x + 8 is 11, then the value of x is

Try yourself: If the mean of x, x + 3, x + 5, x + 7, x + 10 is 9, the mean of the last three observations is

Try yourself: If x is the mean of x₁, x₂, x₃, . . . , x_n, then 

Try yourself: If each observation of the data is increased by 8, then their mean

Try yourself: The mean weight of six boys in a groups is 48 kg. The individual weights of five of them are 51 kg, 45 kg, 49 kg, 46 kg and 44 kg. The weight of the 6th boy is52 k g

Try yourself: The mean of the marks scored by 50 students was found to be 39. Latter on it was discovered that a core of 43 was misread as 23. The correct mean is

Try yourself: The mean of 100 items was found to be 64. Later on it was discovered that two items were misread as 26 and 9 instead of 36 and 90 respectively. The correct mean is

Try yourself: The mean of 100 observations is 50. If one of the observations 50 is replaced by 150, the resulting mean will be

Try yourself: Let x
be the mean of x₁, x₂, . . . , x_n
and y
be the mean of y₁, y₂, . . . , y_n.
If z is the mean of x₁, x₂, . . . , x_n, y₁, y₂, . . . , y_n,
then z = ?

Try yourself: If x is the mean of x₁, x₂, . . . , x_n,
then for a ≠ 0, the mean of ax₁, ax₂, ..., ax_n, x₁/a, x₂/a, . . . , x_n/a,

Try yourself: If x₁, x₂, . . . , x_n are the means of n groups with n₁, n₂, . . . , n_n number of observations respectively , then the mean x of all the groups taken together is

Try yourself: The mean of the following data is 8.

The value of p is

Try yourself: The runs scored by 11 members of a cricket team are
15, 34, 56, 27, 43, 29, 31, 13, 50, 20, 0
The median score is

Try yourself: The weight of 10 students in kgs are
55, 40, 35, 52, 60, 38, 36, 45, 31,44
The median weight is

Try yourself: The median of the numbers 4, 4, 5, 7, 6, 7, 7, 12, 3 is

Try yourself: The median of the numbers 84, 78, 54, 56, 68, 22, 34, 45, 39, 54 is

Try yourself: Mode of the data 15, 17, 15, 19, 14, 18, 15, 14, 16, 15, 14, 20, 19, 14, 15 is

Try yourself: The median of the data arranged in ascending order 8, 9, 12, 18, (x + 2), (x + 4), 30, 31,34, 39 is 24. The value of x is