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                 \ 06-Jan-2025  Bharat Arora   Proof-7             Reader’s Sign _______________________ Date __________





                          1   2   7    3
                    And,    <   <    <
                          3   5   15   5

                                                                        3
                    Now, find the rational number between       7   and  .
                                                                15      5
                                                                        +
                                                  1    7   3   1   79     1   16    8
                                                    ×    +    =  ×        =  ×   =
                                                  2    15  5   2     15   2   15   15
                                                      7       3     8
                \  The rational number between           and   is     .
                                                     15       5    15

                             7    8    3      1   2   7    8    3
                    Clearly,    <    <    ⇒     <   <    <    <
                             15   15   5      3   5   15   15   5
                                                               1      3       2   7       8
                    Thus, three rational numbers between   and   are:  ,             and     .
                                                               3      5       5  15       15

                      Continuing in this manner, we can find as many rational numbers as we want between the two
                                        1      3
                    rational numbers   and  .
                                        3      5
                   • By using the common denominator

                                                                    −3       1
                    Let us find three rational numbers between          and  .
                                                                     4       5
                    First, convert them into equivalent rational numbers. As the LCM of 4 and 5 is 20.

                                −×35     −15       14      4
                                                    ×
                    Therefore,         =      and       =
                                 45      20        54     20
                                  ×
                                                    ×
                      Clearly,  −15  <  −14  <  −13  <  −12  < ...  < <  1  <  2  <  3  <  4  , we can take any three rational numbers
                                                         0
                             20    20     20    20           20   20   20   20
                                                          1
                    like:  −14  , −13 1   between   −3   and  .
                                   ,
                          20   20 20              4       5
                    However, we can find unlimited (infinite) rational numbers between any two rational numbers.

                         Practice Time 1A




                  1.  Convert the rational number   4   into equivalent rational number with
                                                    5
                    (a)  denominator = 15                               (b)  denominator = –20

                    (c)  numerator = 28                                 (d)  numerator = –8
                        2                          22
                  2.  Is    the standard form of  −  ? Give reason in support of your answer.
                        − 5                        55
                                −3      1
                  3.  Represent     and    on the same number line.
                                8       4

                                −12      12
                  4.  Represent      and     on the same number line. Are these points equidistant from the origin?
                                 5        5

                                                                   13                                    Rational Numbers
   10   11   12   13   14   15   16   17   18   19   20