Page 65 - classs 6 a_Neat
P. 65

1     2      5      9
 3  3  12 3  9  EXAMPLE 8:   2  ,3    ,4     ,5      , etc., are all mixed fractions.
 Short Method  of 12 =   [  ×  ]  =  = 9.  3  5  7  11
 4  4  1  1
 1
 5      TO CONVERT A MIXED FRACTION INTO AN IMPROPER FRACTION
 EXAMPLE 3:  Find  8  of 32.


 5  5  32 4  20               A mixed fraction = A whole number + Afraction.
 SOLUTION:   of 32 =   [  ×  ]  =  = 20.
 8  8  1  1                    3         3       (2 × 5) + 3      13         4         4       (3 × 7) + 4      25

 1      EXAMPLE 9:  (i)     2     = 2 +       =                =         (ii) 3  = 3 +     =                 =
                               5         5            5            5         7         7            7            7
        RULE: Multiply the whole number with the denominator of the fraction and to this product add the numerator
 EXAMPLE 4:    What fractton of a day ts 8 hours?  of the fraction. This gives the numerator of the required improper fraction. Its denominator is the same as the
 SOLUTION:      We know that 1 day = 24 hours.  denominator of the fractional part.

 8      TO CONVERT AN IMPROPER FRACTION INTO A MIXED FRACTION
  the required fraction =
 24

        EXAMPLE 10:           Convert  29   into a mixed fraction.
 EXAMPLE 5:   What fraction of an hour ts 40 minutes?  8
                              On dividing 29 by 8, we get quotient = 3 and remainder = 5.
 SOLUTION:    We know that 1 hour = 60 minutes.  29  5    5       3

                                       8   = 3 +  8  = 3  8  = 3  8
 40
  the required fraction =    .
 60                                      38         2       2
                              Similarly,     = 4 +     = 4
 1                                       9          9       9
 EXAMPLE 6:    In the givenfigure, if we say that the shaded region is    of the whole, then what ts       TO REPRESENT MIXED FRACTIONS ON NUMBER LINE
          the error in it?  2
 SOLUTION:    In the given figure, the shaded region is not equal to the unshaded region.  o           C
        EXAMPLE 11:           Represent  2  2  on the number line.               A       B   P
 1                                          5                              0     1       2 2  2        3
  shaded region is not equal to     of the whole.  SOLUTION:    Let OA = AB = BC = 1 unit.   5
 2
                              Then, clearly, OB = 2 units and OC = 3 units.
                              Divide BC into 5 equal parts and take 2 parts out of them to reach the point P.
 PROPER, IMPROPER AND MIXED FRACTIONS
                                                                  2
                              Clearly, P represents the number  2   •
 PROPER FRACTIONS A fraction whose numerator is less than its denominator is called a proper fraction.  5


 2  5  7  0  8                                    SOLVED EXAMPLES
 EXAMPLE 7:       ,  ,  ,  ,   etc., are all proper fractions.
 5  8  11  4  15
 Note:        Each proper fraction is less than 1.  EXAMPLE 12:    Write six improper fractions with denominator 7.

        SOLUTION:             Clearly,   8   9     10    11     12    13  are all improper fractions,
 IMPROPER FRACTIONS A fraction whose numerator is greater than or equal to its denominator is called an   each with denominator 7.  7  ,  7  ,  7  ,  7  ,  7  ,  7
 improper fraction.


 5  7  8  10  11  25
 Thus    ,  ,  ,  ,  ,           etc., are all improper fractions.  EXAMPLE 13:    Write six improper fractions with numerator 11.
 4  3  5  10  6  9                     11    11    11     11    11     11    11
        SOLUTION:             Clearly,     ,     ,     ,      ,     ,      ,             are all improper fractions
 MIXED FRACTIONS A combination of a whole number and a proper fraction is called a mixed fraction.  with numerator 11.  2  3  3  4  5  6  7
   60   61   62   63   64   65   66   67   68   69   70