Page 76 - ICSE Math 5
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•  Equivalent fractions: Fractions which have
                          the same value or represent the same part
                          of a whole are called equivalent fractions.
                                                     4
                                        1 2 3
                         For example,  ,  ,   and   are equivalent
                                        2 4 6        8        1   2          1            2           3            4
                          fractions. They can be written as   =   =          2            4           6            8
                                                              2   4
                              4
                          3  =  .
                          6   8
                     •  Proper fractions: Fractions in which the                             Top Tip
                          numerator is less than the denominator                •   The value of a proper fraction is
                          are called proper fractions.                            always less than 1.
                          For example,   11 5   ,   6 18  and   3   are         •   The value an improper fraction is
                                                    ,
                                           ,
                                         18 19 11 19           14                 always greater than or equal to 1.
                          proper fractions.
                     •  Improper fractions: Fractions in which the numerator is greater than or equal to the
                          denominator are called improper fractions.

                          For example,  13 3 21 17     and  11  are improper fractions.
                                           ,  ,
                                                  ,
                                         5 2 19 10         11
                     •  Mixed fractions: Fractions which are a combination of a whole number and a proper fraction
                          are called mixed fractions or mixed numbers.

                                          4    7     4        8
                          For example, 3    , 2  , 1    and 7    are mixed fractions.
                                         17    15   19       11
                    Reciprocal of a Fraction

                    The reciprocal of a fraction is obtained by turning the given fraction upside down or by
                    interchanging the numerator and the denominator of the fraction. For example, the reciprocal
                       7    15                        1    3
                    of    is    and the reciprocal of   is  .
                      15     7                        3    1
                    Finding Equivalent Fractions

                    We can find the equivalent fractions of a given fraction in two different ways.

                       1. By multiplying both the numerator and the denominator of the fraction by the same
                           number (other than 0).
                                                                                 1
                           For example, let’s find three equivalent fractions of   by multiplying.
                                                                                 3
                                                       3 1
                           1  =   1 × 2  =  ;   =  1 × 3   =  ;   =   1 × 4   =   4
                                        2 1
                           3   3 × 2    6 3    3 × 3   9 3    3 × 4    12
                               2 3       4                                   1
                           So,   ,    and    are the equivalent fractions of  .
                               6 9       12                                  3
                                                       1   2   3    4
                           This can also be written as   =   =   =    .
                                                       3   6   9   12
                       2. By dividing both the numerator and the denominator of the fraction by the same number
                           (other than 0).

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