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            Comparison of Fractions

            In like fractions, the fraction with the larger numerator is greater.
                            23    12
            For example,        >     as the numerator 23 of the first fraction is greater than the numerator of
                            25    25
            the other fraction, which is 12. That is 23 > 12.
            In unlike fractions, first, we change the fractions into                 We convert a group of unlike
            like fractions or their respective equivalent fractions                  fractions to like fractions, or to
            with the same denominator by finding the LCM of the               Note:   equivalent fractions having a
            denominators of the given fractions and compare them                     denominator equal by taking he
                                                                                     LCM of the denominators of the
            as like fractions.                                                       given fractions.
                                             2       4
            For example: Let us compare   and  .
                                             7       5
            First, we find the LCM of the denominators 7 and 5, which is 35.
                   2    2 ×  5 10       4    4 ×  7  28
            Now,   =         =     and     =       =
                   7    7 ×  5 35       5    5 ×  7  35
                                      10   28
            Q 10 < 28. Therefore,     35  <  35
                    2   4
            Thus,   <
                    7   5



                    Enrichment

                 We have another way to compare the unlike fractions.
                     a
                 Let   and   c   be two unlike fractions, by cross-multiplication of both fractions.
                     b      d              a      c

                                           b      d
                                     a   c                          a   c
                   (i) If ad > bc, then   >       (ii) If ad < bc, then   <
                                     b   d                          b   d
                   (iii)  If ad = cd, then   a  =  c   (we can say these are equivalent fractions)
                                      b  d

            Ordering of Fractions

            In a class, Varun, Dinesh, Maya and Sonam are friends, they are walking on a track. They decided
            to check their strength by covering their walking distance in 10 minutes.
                            3                    5                 2                      1
            Varun covers       , Dinesh  covers  , Maya covers   and Sonam covers   of the walking track in
                            10                   8                 5                      3
            10 minutes. Who covers the maximum part of the track?

            Arrange the following fractions in ascending order. Let us find the LCM of the denominators
            10, 8, 5 and 3 is 120. Write the fractions into like fractions with denominator 120.
                                                               ×
                                           ×
                                    3  =  312    =  36  ;  5  =  515  =  75
            As,                     10   10 12     120 8     815      120
                                                               ×
                                            ×
                                         ×
                                                               ×
                                   2  =  224  =  48  ;   1  =  1 140  =  40
                                                               ×
                                         ×
                                   5   524      120      3   340      120
            Mathematics-7                                      32
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