The mean and standard deviation of 20 observations are found to be 10 and 2, respectively. On rechecking, it was found that an observation 8 was incorrect. Calculate the correct mean and standard deviation in each of the following cases: (ii) If it is replaced by 12.

Find the mean deviation about the mean for the data:

The mean and standard deviation of 20 observations are found to be 10 and 2, respectively. On rechecking, it was found that an observation 8 was incorrect. Calculate the correct mean and standard deviation in each of the following cases: (i) If wrong item is omitted.

Find the mean and variance for: First 10 multiples of 3

Find the mean, variance and standard deviation using short-cut method Height in cms:

Find the mean deviation about the mean for the data:

 

The mean and variance of eight observations are 9 and 9.25, respectively. If six of the observations are 6, 7, 10, 12, 12 and 13, find the remaining two observations.

Find the mean deviation about the mean for the data:
$x_i$: 5 10 15 20 25
$f_i$: 7 4 6 3 5

The diameters of circles (in mm) drawn in a design are given below:

Calculate the standard deviation and mean diameter of the circles. [ Hint First make the data continuous by making the classes as 32.5-36.5, 36.5-40.5, 40.5-44.5, 44.5 - 48.5, 48.5 - 52.5 and then proceed.]

Find the mean deviation about median for the following data:

 

Calculate the mean deviation about median age for the age distribution of 100 persons given below:

[Hint Convert the given data into continuous frequency distribution by subtracting 0.5 from the lower limit and adding 0.5 to the upper limit of each class interval]

The mean and variance of 7 observations are 8 and 16, respectively. If five of the observations are 2, 4, 10, 12, 14. Find the remaining two observations.

Find the mean deviation about the mean for the data: 38, 70, 48, 40, 42, 55, 63, 46, 54, 44

Find the mean deviation about the median for the data:
$x_i$: 15 21 27 30 35
$f_i$: 3 5 6 7 8

Find the mean and standard deviation using short-cut method.

Find the mean deviation about the mean for the data: 4, 7, 8, 9, 10, 12, 13, 17

Find the mean deviation about the mean for the data:
$x_i$: 10 30 50 70 90
$f_i$: 4 24 28 16 8

Find the mean deviation about the median for the data: 36, 72, 46, 42, 60, 45, 53, 46, 51, 49

The mean and standard deviation of a group of 100 observations were found to be 20 and 3, respectively. Later on it was found that three observations were incorrect, which were recorded as 21, 21 and 18. Find the mean and standard deviation if the incorrect observations are omitted.

Find the mean and variance for the data: