In: Statistics and Probability
In this case we have to construct the frequency table of the data with set of values 5,9,11,14,15,17,19,23 with 5 as a starting point and 7 as a width of class of interval. Here, we have class of equal width of 7 and the class is created in such a way that the in each class lower limit is included in the class where as upper limit excluded so in 5-12 class of width 7, 5 is included and 12 excluded. Then, we have given the frequency table as
The frequency histogram with labels and mid point of the class is given below
Now, we obtain the mean using the frequency table. For this let us consider
For given class and the frequency table, we have the mean and variance as
Therefore we first calculate the mean using the above table.
Once we have obtained the mean the variance can be obtained by making use of the table below
Using the formula and the above table we have variance and standard deviation as