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(a)  Which goal is possessed by maximum number of students?
                  (b)  Which goal is possessed by the least number of students?
                  (c)  Which goal has the highest rate of being fulfilled?
                  (d)  Which two goals have equal chances of being fulfilled?
                  (e)  Which goal can be termed as the modal goal?


                                                    Maths Lab Activity

              Objective: To collect data, convert it into frequency distribution and find its central tendencies

              Step 1:  Collection of data                                                          Number
                         Collect the measure of weights of all the students of           Weight       of
                         your class.                                                     (in kg)   students
              Step 2:  Organize the data so collected.                                     36

                         •  Make a table, similar to the one shown here to record          37
                            your data.                                                     38
                         •  Mark each student’s weight with a tally mark (|)               39
              Step 3:  Study the data                                                      40
                                                                                           41
                          See whether your weight is more, less or about the same          42
                         as that of other students in your class.                          43
              Using the data so collected, answer the following questions:                 44
              1.  What is the highest and lowest weight in your class?                     45

              2.  Is your weight near the highest or lowest weight? Also find the range of the data.
              3.  Find the mean weight of the students of your class.

              4.  Would you choose mode or median to describe a typical student’s weight? Why?
              5.   What if the weight of two thinly built, frail students is excluded from the data as they
                  leave the class?

                   (a)  Do you think the median would remain the same or change? Explain why this would
                        happen?
                   (b)  What is the likelihood of the mode remaining the same or changing? Justify.

                   (c)  Is the teacher right in saying that the mean weight of the class will decrease?

                                                    At a Glance

              1.  A collection of numerical facts about an information is called data. Each numerical figure in
                 a data is called an observation.

              2.  Series of individual observations is called raw data.
              3.  The number of times a variable occurs in a data is called its frequency. Raw data can be
                 converted into frequency distribution table also known as discrete series.

              4.  Collection, recording and presentation of data help us to organize our information and draw
                 inferences from them.


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