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A data matrix consisting of marks obtained by students in half-yearly exam will look as follows:

                                English        Mathematics         Physics         Chemistry      Computer Science
                   Student   Theory ASL  Tot  Theory Prac  Tot  Theory Prac  Tot  Theory Prac  Tot  Theory Prac  Tot  %
                    Name                                                                                           age
                            [80]  [20] [100]  [80]  [20]  [100]  [70]  [30]  [100]  [70]  [30]  [100]  [70]  [30]  [100]
                      A     70    18    88    66    17   83     13    24   37    47    28    75    41    19   60   68.6
                      B     68    15    83    43    12   55     35    23   58    37    20    57    21    18   39   58.4
                      C     62    17    79    56    13   69     21    25   46    36    22    58    42    19   61   62.6
                      D     70    18    88    79    20   99     62    28   90    68    29    97    63    25   88   92.4
                      E     68    16    84    34    11   45     27    23   50    41    28    69    23    19   42    58
                      F     71    17    88    75    20   95     57    27   84    66    27    93    65    26   91   90.2
                      G     67    16    83    50    14   64     29    24   53    43    25    68    31    20   51   63.8
                      H     69    15    84    54    17   71     35    26   61    46    27    73    50    22   72   72.2

                 In the above example, student name, English theory marks, ASL marks, etc. are variables and each row represents a
                 single case (student).

                 Frequency Tables
                 The frequency of a particular data value is the number of occurrences of that data value in a dataset. Let's say that if five
                 students achieved 95 marks in the maths exam, then the score of 95 has a frequency of 5.
                 The frequency of a data value is often represented by 'f'. A frequency table is created by ordering the collected data
                 values in ascending order of magnitude or in descending order with their respective frequencies.

                 Example 1: The following shows the number of chocolates eaten by students of a class on a particular day. Create a
                 frequency table for this data:

                                       6     3     2     1      3     2      5      6      2    2

                                       4     4     1     3      1     6      3      1      2    6
                                       2     4     5     5      4     5      6      3      5    4

                 The frequency table of the above data is as follows:

                                                      Chocolates   Tally  Frequency
                                                          1        ////       4
                                                          2          /        6
                                                          3        ////       5
                                                          4        ////       5
                                                          5        ////       5
                                                          6        ////       5
                                                        Total       30        30


                 Example 2: The following shows marks scored by XI class students in the Physics Half Yearly exam. Create a frequency
                 table for this data.

                                                 37     58     46      90     50     84
                                                 53     61     44      38     54     57
                                                 59     19     89      49     66     50
                                                 53     81     63      48     71     51
                                                 52


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