Page 27 - ICSE Math 7
P. 27

2            Fractions











                   Key Concepts

                         • Fractions                                         • Reciprocal of a Fraction
                         • Classification of Fractions                       • Fraction as an Operator
                         • Reducing a Fraction to Its Simplest Form          • Continued Fraction
                         • Like and Unlike Fractions                         • Simplification of Complex Fractions
                         • Comparison of Fractions                           • Simplification of an Expression
                         • Inserting a Fraction between Two Fractions        • Word Problems
                         • Fundamental Operations on Fractions


                    Fractions
                                                                               m
                    A fraction represents a part of a whole. It is represented by  , where m and n are
                                                                               n
                                                           m
                    whole numbers and n ≠ 0. The fraction   represents m parts out of n equal parts.
                                                            n
                                 m
                    In a fraction  , m is called the numerator and n is called the denominator. For
                                 n
                    example, if a circle is divided into 4 equal parts, then each part is one-fourth of
                                                                                 1
                    the whole circle and each part is represented by the fraction  .
                                                                                 4
                    Classification of fractions
                    Proper fraction
                    A fraction whose numerator is less than its denominator is known as a proper fraction. For example,

                    1 17   and  35  are proper fractions.
                       ,
                    2 19        36
                    Improper fraction

                    A fraction whose numerator is greater than or equal to its denominator is known as an improper
                                           8
                    fraction. For example,   ,  11   and  17   are improper fractions.
                                           7   10       14
                    Mixed fraction

                    A fraction which consists of a whole number and a proper fraction is known as a mixed fraction.
                                    1
                                         7
                    For example, 2   , 3    and 2  11   are mixed fractions.
                                    4    8       17
                    Any mixed fraction can be converted into improper fraction by using the formula:

                                                         Numerator       (Whole part × Denominator) + Numerator
                        Mixed fraction = Whole part +                  =
                                                        Denominator                     Denominator

                    Also, an improper fraction can be converted into a mixed fraction by using the formula:
                                                                                Remainder
                                               Improper fraction = Quotient   Denominator



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