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E:\Working\Focus_Learning\Math_Genius_5_(05-10-2023)\Open_Files\CHAP_04
              \\November 22, 2023 3:12 PM   Surender Prajapati   Proof 5   Reader _________________________   Date: ___________________74





              example 2:  Compare the following.
                                3
                        2
                                                                         7
                    (a)   and                                        (b)   and    4
                        5       4                                        9       27
              Solution:     (a)   First,  we have to  change the given fractions  into  their  respective
                                 equivalent  fractions  having  the  same  denominator equal  to the  LCM of

                                 the denominators of the given fractions.
                                 Now, find the LCM of the denominators 5 and 4.

                                 LCM of 5 and 4 is 20.
                                                                      3
                                              2
                                 Therefore,  =     2 × 4  =   8   and   =  3 × 5  =   15
                                              5    5 × 4     20       4    4 × 5     20
                                 Since, 15 > 8

                                 So,  15  >   8
                                      20     20
                                         3
                                 Thus,  >     2
                                         4    5

                            (b)   Change the given fractions into their respective equivalent fractions having
                                 the same denominator equal to the LCM of the denominators of the given
                                 fractions.
                                 Now, find the LCM of the denominators 9 and 27.

                                 LCM of the denominators 9 and 27 is 27.
                                         7
                                 Then,  =     7 × 3  =   21  and   4   =   4 × 1   =   4
                                         9    9 × 3     27       27     27 × 1     27

                                 Since, 21 > 4
                                 So,  21  >   4
                                      27     27
                                         7
                                 Thus,  >     4  .
                                         9    27

              example 3: Which is greater       3 5  or   3 3 ?
                                                  6       4                                         2 6, 4

              Solution:     We have,    3 5  =   3 × 6 + 5  =   18 + 5  =   23                      2 3, 2
                                          6         6            6        6                         3 3, 1


                                  and   3 3  =   3 × 4 + 3  =   12 + 3  =   15                         1, 1
                                         4         4            4        4                    LCM = 2 × 2 × 3 = 12

                            LCM of 6 and 4 is 12.

                            Now,   23  =  23 × 2   =   46  and   15  =  15 × 3   =   45
                                    6      6 × 2     12        4      4 × 3      12           Remember
                                                    46    45        23     15           To compare mixed fractions,
                            Clearly, 46 > 45, so    12  >   12  i.e.,   6   >   4       first convert them into

                            Thus,  3 5  >  3 3 .                                        improper fractions and then
                                                                                        compare them as usual.
                                     6      4

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