Page 131 - Data Science class 10
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2.   Remove one snap cube from the highest stack and place it on one of the lowest stacks, continuing until
                 all the stacks are leveled out.
              Both these approaches yield an equal family size of three, which we can consider as an equal share or a fair
              share.
              For the second approach, you can start with removing a snap cube from the highest stack and placing it on
              one of the lowest stacks. This will result in a new arrangement of cubes as shown in the figure given below.


















                                              Moving one snap cube from the highest stack
              We will continue this process until all the stacks are level, or nearly level when there is a remainder as shown
              in the figure given below.










                                             Snap cubes representing an average family size
              After the final move, all five stacks are levelled with three cubes each. This represents that the family size
              of three is an equal share. That means, if all five family sizes were the same, the number of people in the
              household would have been three. This equal share is nothing but the mean of the distribution.
              By now, we know how to calculate the mean by adding up all the observations and dividing it by the
              number of observations. However, we still need to find answers to the questions given ahead. What does
              mean tell us about the distribution? How are we expected to interpret the mean? How are we expected to
              describe the variability in a distribution in relation to its mean?
              We can investigate the following problem to get an
              answer to these questions:                           Group 1
              Suppose  two  other  groups  of  five  students  in  the
              classroom found their equal share value to be six. What
              are some different snap cube representations that they
              could have constructed?
              To  answer  this,  we  should  first  realise  that  we  need  to
              start with 30 snap cubes. We can then create two different
              distributions of family size where the equal share value is 6.
              For example, consider the following two groups, Group 1
              and Group 2 (shown in  the two figures given below) of data
              on  five  family  sizes  from  the  classroom  where  the  equal
              share family size for each group is 6.

                                                                               Group 1 arrangement with average 6

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