Page 82 - classs 6 a_Neat
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EXAMPLE 6:            Simplify: 5  1    - 3  1  + 3  1  + 4.                                                                                                     4     1
                                           6        4        4                                                                     JUST TRY1:           Find the sum of   9  +  9  .
        SOLUTION:             we have:
                                    1        1        1                        [ 12 ÷ 6 = 2, 2 × 31 = 62] ,                        JUST TRY 2:                             1          2   .
                                5       - 3      + 3     + 4.                                                                                           Find the sum of 3  5  and 6   5
                                    6        4        4                 {      [ 12 ÷ 4 = 3, 3 × 13 = 39]   }

                                   31        13     10     4                   [ 12 ÷ 3 = 4, 4 × 10 = 40]                                                         6          13
                                =        -       +      +                                                                          JUST TRY 3:          Subtract      from       .
                                    6        4      3      1                   [ 12 ÷ 1 = 12, 12 × 4 = 48]                                                        15         15
                                   62 - 39 + 40 + 48                                                                                                                 1          2
                                =                                                                                                  JUST TRY 4:          Subtract  1     from 5    .
                                          12                                                                                                                         3          3
                                   150 - 39     111 37    37        1                                                                                         2       3
                                =            =         =       = 9                                                                 JUST TRY 5:          Add      and    .
                                      12         12        4        4                                                                                         3       5
                                                    4
                                                                                                                                                                 3         1
                                                                                                                                   JUST TRY 6:          Add 2       and 4    .
                                                                                                                                                                 4         8
                                   5         9
        EXAMPLE 7:            Of,      and     which ts greater and by how much?
                                   7        14                                                                                                                           PRACTICE EXERCISE 5.3
                                              5         9
        SOLUTION:             Let us compare      and
                                              7        14
                              5 × 14 = 70 and 7 × 9 = 63.                                                                          1 . Add the following fractions and reduce them to the lowest terms.
                                               5       9                                                                                       5      3        3      5       1        3      2       1          5       3        1
                              Clearly, 70 > 63;    >                                                                                      (a)  12  +  12  (b)  11  +  11  +  11   (c)  7  +   5   +  10  (d) 1   8  + 2  4  + 3  12
                                               7      14

                                                    5       9                                                                             (e)  2 + 3  1  + 4  1  + 5  1
                              Required difference =  7  -  14                                                                                         2       3       4
                                      10 - 9                                                                                       2. Subtract the following fractions and reduce them to the lowest terms.
                                   =                             {     [ 14 ÷ 7 = 2, 2 × 5 = 10]  and  }
                                        14                             [ 14 ÷ 14 = 1, 1 × 9 = 9]                                          (a)  8   -  4   (b)  11  -  9   (c) 5  2  - 3  1   (d) 3  3  - 1  1   (e) 7  1  - 4  1
                                        1                                                                                                     15     15        25     25         3       3          5       15         6       18
                                   =
                                        4
                                                                                                                                   3. Simplify the following and reduce them to the lowest terms.

                              Hence,  5    is greater than.  9  by  1                                                                     (a)  4  +  2  -  3  (b)  11  -   4   +  6   (c) 3  1  + 2   4  - 1  1   (d) 3  21  +   201  -   431
                                      7                 14       14                                                                           5      5     5       21     21      21         2        5       2         10      100      200

                                                      2                            1                                                      (e) 4  3  +  2  5  - 1  1
        EXAMPLE 8:            The cost of a pen is ₹ 6   and that of a pencil is ₹  4  6  Which costs more and by how                           35        7      5
                              much?                   3                                                                            4. Tapur and Tupur anted to gift a shawl to their mother. Tapur knitted  3  th   of  the shawl and Tupur  1
                                                   2     20        ( 20 × 2 )    40                                                                                                                    5                             5  th
        SOLUTION:             Cost of a pen = ₹   6  = ₹        = ₹          =                                                      is the shawl complete? If not, how much of the knitting is yet to be done for the gift to be ready?
                                                   3      3        ( 3 × 2 )     6                                                                                                      1                     1
                                      40      25             2       1                                                             5. Seema and Reena go for jogging. Seema jogs for 2  5   km and Reena   2  7  km. Who jogs more and by
                              Clearly,    >       and so ₹ 6    > 4                                                                how            much?
                                       6      6              3       6
                              So, the cost of a pen is more than the cost of a pencil.                                             6. Mini bought 5 litres of oil. She used 3  3    litres of oil for cooking during the month. How much oil is left
                                                                                                                                                                            5
                              Difference between their costs = ₹  (   20   -  25   )      (    40 - 25   )                         at the end of the month?               3                      1
                                                                                                                                                      1
                                                                              6
                                                                       3
                                                15         3         1                            6                                7. Vinita bought 5  2   kg of guavas,  3  4  kg of apples and  4  4   kg of oranges. Find the total weight of the
                                                                                                                                   fruits bought by her.
                                            = ₹       = ₹ 2     = ₹ 2   .
                                                 6         6         6
                                                                                          1
                           Hence, the cost of a pen is more than the cost of a pencil by ₹ 2  .
                                                                                          2
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