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7.4 Improper fractions and mixed numbers



               7.4 Improper fractions and mixed numbers


               In a proper fraction the numerator is smaller than the denominator.   An improper fraction is sometimes
               Example:   2                                                        called a top-heavy fraction.
                          3
                                                                                   An improper fraction can be
               In an improper fraction the numerator is bigger than the            written as a mixed number.

               denominator. Example:   4
                                       3
               An improper fraction can be written as a mixed number.                 A mixed number contains a
                                                                                      whole number and a fraction.
                Worked example 7.4

                a  Write the fraction shaded in this diagram as:
                   i  a mixed number      ii  an improper fraction.
                                                                2
                b  i  Write  5  as a mixed number.    ii  Write 4  as an improper fraction.
                           2                                    3
                       1
                a  i  1              1 complete rectangle and   1   of the second rectangle are shaded.
                       4                                     4
                      5               4                           1
                   ii   4               from the fi rst rectangle and  4  from the second gives a total of
                                      4
                                     5 quarters or   5  .
                                                  4
                      5   1           5
                b  i   =  2             is 5 halves. 4 halves makes 2 whole units and there is 1 half left.
                      2   2           2
                   ii  4 2  =  14     Change 4 whole units into thirds: 4 × 3 = 12 so there are 12 thirds.
                       3
                           3
                                     Then add the extra 2 thirds: 12 + 2 = 14 thirds.

               )     Exercise 7.4

               1  Write down the fraction shaded in each of these diagrams as:
                  i  a mixed number        ii  an improper fraction.
                  a                       b                            c


                  d                       e                             f



               2  Write each improper fraction as a mixed number.     a   7       b   13      c   6
                                                                          2            4          5
                                                                           1
                                                                                        1
               3  Write each mixed number as an improper fraction.    a  4        b  2        c  4 3
                                                                           2            3          4
               4   Sita made 5 cakes for a birthday party. She cut each cake into 12 pieces.
                 At the end of the party there were 7 pieces of cake that had not been eaten.
                 Write the amount of cake that was eaten as:
                  a  a mixed number         b  an improper fraction.






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