How to find the Mean and Median of a data set

INTRODUCTION:

           A group of variables or a set of information is referred as Data. In general, sets are the collections of numbers and set can contains any kind of data. Data set is nothing but a collection of data. Data set can be represented as tables and graphs. Data collection is the method of collecting or preparing the data. For a given data set, we can find the mean, median, mode and range which is explained below.

Mean of data set:
         For finding the mean of all the values in a given data set, we have to find the sum of all numbers given in data set and we have to divide the total sum by the total number of elements.
Example:
Find the mean of data set: {8, 18, 23, 35, 51}
Solution:
         Mean      =    Total sum of data set  / Total number of elements in data set
                         =    (8 + 18 + 23 +  35 + 51) / 5
                         = 135 / 5   = 27
Median of a data set:
        In general, median is referred as the middle value of the given data set.
Example 1 :
Find the median for the given values: {5, 6, 9, 25, 34}
Solution:
      Here, the middle value is 9. Hence median = 9.