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EQUIVALENT FRACTIONS
                                                                                                                                   (ii)  5  =   5 × 2   =  5 × 3   =    5 × 4   =   5 × 5
                                                                                                                                         7      7 × 2      7 × 3        7 × 4       7 × 5
        Look at the figures given below.
                                                                                                                                               5  =   10  =  15  =   20  =  25

                                                                                                          1                                    7      14     21      21     35
                                                                                                          2                               Hence, the four fractions equivalent to   5  are  10  ,  15  ,  20  and  25
                                                                                                          2                                                                      7       14      21      21        35
                                                                                                          4                              5       8 × 2      8 × 3        8 × 4       8 × 5
                                                                                                          3                        (iii)   11  =  11 × 2  =  11 × 3  =  11 × 4   =  11 × 5
                                                                                                          6                                    5      16      24      32     40
                                                                                                          4                                    11  =  22   =  33  =   44  =  55

                                                                                                          8                                                                      8       16     24      32        40
        Clearly, the shaded portions of these figures are equal.                                                                          Hence, the four fractions equivalent to    are      ,      ,       and
                  1    2     3     4                                                                                                                                            11       22     33      44        55
               =     =     =     =
                  2    4     6     8                                                                                                                                                 3
                                                                                                                                   EXAMPLE 2:           Write afraction equivalent to     with numerator 15.
        These fractions are called equivalent fractions.                                                                                                      3       15             4
                                                                                                                                   SOLUTION:            Let       =
                   1      1 × 2       1 × 3       1 × 4                                                                                                       4
        Note that     =           =          =
                   2      2 × 2       2 × 3       2 × 4                                                                                                 Clearly, 15 = (3 × 5).

                                                                                                                                                        So, we multiply the denominator also by 5.
        It shows that multiplying the numerator and the denominator of a fraction by the same nonzero number does not                                       3       3 × 5        15
        change the value of the fraction.                                                                                                                       =           =
        Similarly, dividing the numerator and the denominator of a fraction by the same nonzero number does not                                             4       4 × 5        20
        change the value of the fraction.                                                                                                                                              15
        All such fractions are known as equivalent fractions.                                                                                           Hence, the required fraction is    20  •
                                                                                                                                                                                     5
        EQUIVALENT FRACTIONS Two or more fractions representing the same part of a whole are called                                EXAMPLE 3:           Write ajraction equivalent to     with denominator 56.
                                                                                                                                                                                     8
        equivalentfractions.                                                                                                                                         5
                                                                                                                                   SOLUTION:                   Let       =
                                                                                                                                                                     8       56
        RULE:To get afraction equivalent to a givenfraction, we multiply or divide the numerator and the denominator                                    Clearly, 56 = (8 × 7).
        of the given fraction by the same nonzero number.
                                                                                                                                                        So, we multiply the numerator also by 7.

                                                  SOLVED EXAMPLES                                                                                            5   =   5 × 7  =    35
                                                                                                                                                            8        8 × 7       56
        EXAMPLE 1.            Write four fractions equivalent to each of the following.                                                                                                35

                                   3       5        8                                                                                                   Hence, the required fraction is      •
                               (a)    (b)      (c)                                                                                                                                     56
                                   4       7        11                                                                                                                               36

        SOLUTION:              3  =   3 × 2  =   3 × 3   =   3 × 4   =   3 × 5                                                     EXAMPLE 4:           Write fraction equivalent to    63   with numerator 4.
                               4      4 × 2      4 × 3       4 × 4       4 × 5                                                                                36       4

                                  3  =  6  =   9   =  12  =   15                                                                   SOLTUION:            Let   63   =
                                  4     8     12      16      20                                                                                 Clearly, 4 = 36 ÷ 9.


                              Hence, the four fractions equivalent to are   3  ,  6  ,  9  ,  12  and  15                                        So, we divide the denominator also by 9.
                                                                        4     8    12     16        20
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