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FRACTION AS A PART OF A COLLECTION
                                    5                        Fractions

                                                                                                                                   Consider the following figures:



                                      FRACTIONS AND FRACTIONAL NUMBERS



        Look at the given figure.
        In this figure, a strip has been divided into 7 equal parts.
        Out of these 7 equal parts, 4 parts have been shaded.
        Clearly, the shaded portion represents four-sevenths.                  4
                                                                               7                                                                 Fig. (i)                             Fig. (ii)                           Fig. (iii)

                                    4                                                                                              Fig. (i) contains a collection 3 of 8 circles, of which 3 circles are shaded.
        In numeral, we denote it by     (read as Four by seven’).
                                    7                                                                                                                              3
              4                                                                                                                           Shaded circles represent    of the collection.
        Here   is a fraction and four-sevenths is a fractional number                                                                                              8
              7

        FRACTIONS ON NUMBER LINE                                                                                                   Fig. (ii) contains a collection of 12 triangles, of  which 7 triangles are shaded.

                                               4
        Suppose we want to denote the fraction     on the number line.                                                                    Shaded triangles represent   7   of the collection.
                                               7                                 P                                                                                   12
        Take a line segment OA of unit length.                          O         4       A                                        Fig. (iii) contains a collection of 15 squares of which 8 squares are shaded.
                                                                                  7                                                       Shaded squares represent   8   of the collection.
        Divide OA into 7 equal parts and take 4 parts out of it to reach the point P.                                                                              15

        Then, the point P represents the number
                                                                                                                                          In general, we define a fraction as given below.

        Some more examples are given below.
                                                                                                                                          FRACTIONS The numbers of the form       a  , where a and b are natural numbers, are called fraction.
                                                                                                                                                                                  b
                     Fraction           Fractional number                                  Number line                                                                                                       a
                                                                                                                                          Here, a is called the numerator and b the denominator of the fraction    ·
                        1                    one - half       1                         O        1       A                                                                                                   b
                        2                                     2                                  2                                                          5
                        1                                     1                         O             1  A                         EXAMPLE 1:           (i)  9  is a fraction with numerator= 5 and denominator= 9.
                        4                  one - quarter      4                                       4

                        2                   two - thirds      2                         O             2  A                         EXAMPLE 2:           (ii)  8  is a fraction with numerator = 8 and denominator = 1
                        3                                     3                                       3                                                      17
                        3                  three - fifths     3                         O           3    A                         FRACTIONAL PART OF A COLLECTION
                        5                                     5                                     5                                                      3
                        5                  five - eighths     5                         O         5      A                         EXAMPLE 3:  Find        4  of 12.
                        8                                     8                                   8
                                                                                                                                   SOLUTION:            Consider a collection of 12 balls.
                                                                                                                                                        Divide this collection into 4 equal parts and take
        Thus, the fractions shown above are   1 1 2  ,   3  and  5  .                                                                                   3 parts out of it.
                                              ,
                                                  ,
                                            2 4 3      5      8                                                                                         CLearly, 3 parts out of 4 parts contain 9 balls.
        The corresponding fractional numbers are one-half, one-quarter, two-thirds, three:ffjths and five-eighths                                       z   8  of 12 balls = 9 balls.
        respectively.                                                                                                                                      17
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