Page 136 - Start Up Mathematics_6
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1        1    2 × 4    1   8    1    8 + 1   9
                                      2  = 2 +   =         +   =   +   =          =
                                       4        4      4      4   4    4      4     4


                We can convert a mixed fraction into an improper fraction as follows:
                             Numerator      (Whole part × Denominator) + Numerator
                Whole part   Denominator   =              Denominator
                      q   p × r + q               1    2 × 4 + 1   9
                i.e., p  =           For example, 2  =           =
                      r       r                   4        4       4


                                             1 3 4 7 9
            Example 11: Locate the points  ,  ,  ,  ,   on a number line.
                                             5 5 5 5 5

            Solution:
                                0      1              3       4      1              7              9       2
                                       5              5       5                     5              5
            Example 12: Express the following as mixed fractions:

                               17                   23                    23                   35
                          (a)                   (b)                  (c)                   (d)
                               4                     5                    7                     9

                               17     1             4                    23      3             4
            Solution:     (a)     = 4             4   17             (b)     = 4            5   23
                               4      4           –16                     5      5           –20

                                                      1                                          3

                                                    3                                          3
                               23     2                                   35     8
                          (c)     = 3            7   23              (d)      = 3           9   35
                               7      7           –21                     9      9           –27
                                                      2                                         8

            Example 13: Express the following as improper fractions:
                                2                                           6
                          (a)  6                                     (b)  12
                                5                                           7
                                2    6 × 5 + 2    32                        6    12 × 7 + 6    90
            Solution:     (a)  6  =             =                    (b)  12  =              =
                                5        5        5                         7         7         7



             EXERCISE 7.1

               1.  What fraction of an hour is 25 minutes?

               2.  What fraction of a week is 3 days?
               3.  A painter is required to make 21 portraits for a business tycoon. He has already made 14
                  of them. What fraction of the total portraits has he made so far?
               4.  Write natural numbers from 1 to 50. What fraction of them are prime numbers?

               5.  Locate the following points on a number line.
                      1 3 5 6                  1   2   5    7
                  (a)  ,  ,  ,            (b)    ,   ,   ,
                      6 6 6 6                 10 10 10 10


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