Page 191 - Ganit Kaushal
P. 191

1
                  The fraction of the roti each child got is  .
                                                         4
                  This situation can also be expressed through division facts, addition facts
                  and multiplication facts as follows:
                                             1
                  The division fact is 1 ÷ 4 =
                                             4

                                         1    1    1    1
                  The addition fact is 1 =   +   +   +
                                         4    4    4    4
                                                   1
                  The multiplication fact is 1 = 4 ×
                                                   4
                                1     1
                  The fractions   and   are called unit fractions. In simple words, if the numerator is ‘1’, then the fraction is
                                2     4
                  called a unit fraction or fractional unit.
                  It is easy to understand that if two children share a roti, they will each receive a larger portion than if four
                                                        1    1
                  children share the same roti. Therefore   >  .
                                                        2    4
                  We conclude, ‘the lesser the denominator, the greater is the fractional unit’. This way, we can easily compare
                  two different fractional units.


                  Fractional Units as a Part of the Whole

                  Now, what if three rotis are shared equally among four children?

                          What is the share of each child?
                          How can this be done? Can you answer it?

                          Well, the answer is simple and can be given in the same manner as done earlier. If three rotis are to
                                                                                    3
                          be shared equally by four children, each will get a share of    i.e.,
                                                                                    4
                          4 parts make 1 whole roti, and each child will have 3 such parts.
                                         3            1        1    1    1   1
                  Also, we can write it as   = 3 times   = 3 ×   =   +   +
                                         4            4        4    4    4   4
                                                                      1
                  That is, each child will get 3 parts of a fractional unit  .
                                                                      4
                  This is interpreted as each roti is divided into four equal parts, and each child
                  will get 3 parts of it (see figure).



                          Remark
                                     3                                                           1
                        The fraction    is read as ‘3 quarters’ or ‘3 upon 4’, but reading it as 3 times    helps us understand the
                                     4                                                           4
                                                                                  1
                        size of the fraction. It clearly shows what a fractional unit is       , and how many times (3 times) such a
                                                                                  4
                                                                                 
                        fractional unit is used.


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