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SAI International School
                                                    CLASS - VIII

               Mathematics
               CHAPTER-5: DATAHANDELING(Lesson Notes- 1)



               SUBTOPIC : INTRODUCTION WITH BAR GRAPH

                       1. Data Handling: Deals with the process of collecting data, presenting it and
               getting result.


                     Data mostly available to us in an unorganised form is called raw data.
                     Frequency gives the number of times that a particular entry occurs.
                     Raw data can be ‘grouped’ and presented systematically through ‘grouped
                       frequency distribution’.
                     Statistics: The science which deals with the collection, presentation, analysis
                       and interpretation of numerical data.
                     Observation: Each entry (number) in raw data.
                     Range: The difference between the lowest and the highest observation in a
                       given data.
                     Array: Arranging raw data in ascending or descending order of magnitude.
                     Data can also presented using circle graph or pie chart. A circle graph shows
                       the relationship between a whole and its part.
                     There are certain experiments whose outcomes have an equal
                       chance of occurring.
                     A random experiment is one whose outcome cannot be predicted
                       exactly in advance.
                     Outcomes of an experiment are equally likely if each has the same
                       chance of occurring.
                     Frequency: The number of times a particular observation occurs in
                       the given data.
                     Class Interval: A group in which the raw data is condensed.
                      Bar Graph: A display of information using bars of uniform width,
                       their heights proportional to the respective values.
                        Double Bar Graph: A bar graph showing two sets of data
                       simultaneously. It is useful for the comparison of the data.















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