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            Let us represent them on number line and write the numbers between these two rational numbers.

                            −3  =  −1                          4  =  2
                            6    2                             6  3                       To write the rational numbers
                                                                                          between two rational
                                                                                  Note:  numbers always covert the
                –1  −5   −4   −3  −2   −1    0    1    2    3   4    5    1
                     6   6    6    6    6         6    6    6   6    6                    given rational numbers with
                                                                                          same denominators.
                      −2  −1     1 2 3                                          −1       2
            Clearly,     ,    0 , ,,  ,   are the rational numbers between          and  .
                      6    6     6 6 6                                           2       3

                                                                     −15       20
            We can also write these given rational numbers  as            and     , respectively.
                                                                     30        30
                                 −15    −14    −13    −12          1    2     3       19    20
            Now, we can write         <      <      <     ... < <    <     <    < ... <   <     rational numbers
                                                              0
                                  30     30     30    30          30    30   30       30    30
            between them.
                                                       −1       2                           −30       40
            Similarly, the given rational numbers          and     can also be written as        and      and so on
                                                       2        3                           60        60
            and we can find many more rational numbers between them.
            Hence, we can find unlimited (infinite) rational numbers between any two rational numbers.
            Example 7: Write five rational numbers between:

                            −4        7               −5       −3
                       (a)      and              (b)       and
                            13       13                7        8

            Solution: (a)  We know that,  –4 < –3 < –2 < –1 < 0 < 1 < 2 < 3 < 4 < 5 < 6 < 7
                                                                       −4       7        −3 −2 −1       0    1
                            Hence, five rational numbers between           and      are:    ,    ,    ,    ,
                                                                       13       13       13   13   13   13 13

                        (b)   The LCM of 7 and 8 is 56.
                            Now, write both the rational numbers with denominator 56.

                            −5  =  −×58  =  −40      −3    −×37     −21
                             7    78        56   and   8  =  87   =  56
                                    ×
                                                             ×
                                     −40    −21
                            Clearly,      <
                                      56    56
                             So, the rational numbers between     −40 and  −21  are:
                                                                  56       56
                            −39  <  −38  <  −37  <  −36  <  −35  < .... <  −20
                             56     56    56     56     56         56
                                                                        −5      −3       −39   −38  −37   −36   −35
                            Thus, the five rational numbers between         and      are:     ,    ,     ,    ,     .
                                                                        7        8        56    56   56    56   56


                     Think and Answer

                                                    3       4
                 Write six rational numbers between   and      .
                                                    4       12


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