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E:\Working\Focus_Learning\Math_Genius-6\Open_Files\10_Chapter_7\Chapter_7
             \ 07-Nov-2024  Bharat Arora   Proof-8             Reader’s Sign _______________________ Date __________





            Addition and Subtraction of Mixed Fractions

            To add or subtract mixed fractions, first convert them into improper fractions.

            Then convert unlike improper fractions into like fractions and then add or subtract as the like
            fractions as usual.
                                     1       1                                         1        1
            Example 16: (a) Add 1  and 6 .                             (b)  Subtract  1  from  6 .
                                     4       2                                         3        2
            Solution: (a)  First convert the mixed fractions into improper fractions.

                             1 5         1   13
                            1 =  and 6     =
                             4 4         2    2
                            The LCM of the denominators 4 and 2 is 4.
                                      ×
                            5   13   51     13 2    5   26   526     31     3           Quick Check
                                              ×
                                                               +
                        ∴     +    =      +       =   +    =       =    =  7
                            4   2    41     22      4   4      4      4     4        Add and subtract as
                                              ×
                                       ×
                        (b)   First convert the mixed fractions into improper        directed and fill in the
                            fractions.                                               empty boxes.
                                                                                                +
                             1 4         1   13
                            1 =  and 6     =                                                 9      8
                             3 3         2    2                                             14     16
                            The LCM of the denominators 3 and 2 is 6.                  –     1      2
                            13  −  4  =  13 × 3  −  42  =  39  −  8  =  31  = 5 1  .         4      5
                                              ×
                                       ×
                                              ×
                             2   3   23      32      6   6   6     6
                                       1     1     1       1
            Example 17: Simplify:  2 −     3   + 4   +− .
                                                       5
                                       5    10    15       3
            Solution:  First convert the mixed fractions into improper fractions:
                           1   11   1    31    1   61
                         2   =    3 ,  =    4 ,  =
                           5   5    10   10   15   15
                         LCM of 5, 10, 15 and 3 = 30
                                                           ×
                                                                   ×
                                                                                  ×
                          11  31   61      1    11 6    31 3    61 2    530     110      66  93   122   150   10
                                                   ×
                                                                          ×
                             −   +    + 5 −  =        −       +       +       −        =    −   +     +     −
                                                           ×
                                                  ×
                                                                                                    0
                                                                          ×
                                                                                  ×
                          5   10   15      3     56     10 3    15 2    130     310      30  30    30    30   30
                                                                   ×
                                                             +
                                                                  −
                                                       +
                                                66 93 122 150 10         235
                                                   −
                                              =                        =
                                                          30              30
                                                47     5
                                              =    =  7 .
                                                 6     6
                                                                                                         2
                                                                            1
            Example 18: Megha bought two packets of biscuits for ` 13  and a cream roll for `16 . Find the
            total money she spent.                                          2                            3
                                                                1     27
            Solution:   Cost of two packets of biscuit = `13  = `
                                                                2     2
                                                                2
                                    Cost of a cream roll = `16  = `   50
                                                                3     3
                                                                               +
                                                              27   50     81 100      181
                                Total cost of both items =  `   2  +  3   = `    6    = `    6 
                                                                                             
                                                                      
                                                                                    
                                                             
                                                        1
                         Thus, Megha spent total ` 30  on both items.
                                                        6
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