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               \ 30-Sep-2025  Bharat Arora   Proof-9                                 Reader’s Sign _______________________ Date __________





 Properties of Multiples  Practice time 5B

 1.  Every number other than zero is a multiple of itself.     1.  Find the first six multiples of:

    Examples:  Multiples of 4 are 4, 8, 12, 16, ...   (a)  5   (b)  7   (c)  11              (d)  13
             Multiples of 5 are 5, 10, 15, 20, ...     2.  Write the first five even multiples of:

             Clearly, 4 and 5 are multiples of themselves.   (a)  17   (b)  13   (c)  15     (d)  25

 2.  Every multiple of a number other than zero is greater than or equal to itself.     3.  Write the following.
    Examples:  Multiples of 6 are 6, 12, 18, 24, ...   (a)  The 5th multiple of 8   (b)  The 8th multiple of 9

             Multiples of 7 are 7, 14, 21, 28, ...
 Think Tank  Logical Thinking  (c)  Multiples of 12 less than 144    (d)  Multiples of 3 between 20 and 50
 3.   There are an infinite (endless or uncountable)   List the first five   (e)  Multiples of 9 between 50 and 100

 number of multiples of a number.   multiples of your age and
    Examples:  Multiples of 7 are 7, 14, 21, 28, ...   your friend’s age taking complete   (f)  The first multiple of 9 which is exactly divisible by 8.
 years.
             Multiples of 9 are 9, 18, 27, 36, ...     4.  Find  the  first  four  common  multiples  of  the  following  numbers.  Then  circle
             Multiples of 10 are 10, 20, 30, 40, ...   the smallest common multiple.

 From the above examples, we can say that there are infinite multiples of any given   (a)  4 and 5   (b)  3 and 5   (c)  2 and 7   (d)  6 and 8   (e)  10 and 20
 number.      test oF DivisiBility

 common Multiples  1  2  3  4  5  6  7  8  9  10  When we divide a number by another number and we get 0 as the remainder, then


 Here the  numbers 1 to  60 are shown  in  11 12 13 14 15 16 17 18 19 20  the number is called divisible by the other number.
 the  grid.  We circle those  numbers red   21 22 23 24 25 26 27 28 29 30  Let us divide both 85 and 88 by 5.
 which  are  the multiples  of  4 and  blue   31 32 33 34 35 36 37 38 39 40  On dividing 85 by 5, we get the remainder 0.  5 85  17  5 88  17
                                                                                                              5
 which are the multiples of 6.  So, 85 is divisible by 5.                                      5              38
                                                                                                35
 Numbers in red circles are: 4, 8, 12, 16, 20,   41 42 43 44 45 46 47 48 49 50                 35             35

 24, 28, 32, 36, 40, 44, 48, 52, 56 and 60.  51 52 53 54 55 56 57 58 59 60  On dividing 88 by 5, we get the remainder 3 instead of 0.  0  3
 Numbers in blue circles are: 6, 12, 18, 24, 30, 36, 42, 48, 54 and 60.  So, 88 is not divisible by 5.

 Numbers in both coloured circles are: 12, 24, 36, 48 and 60.   There are certain tests or rules using which we can tell whether a number is divisible
              by another number or not without actually performing the division.
 Thus, the common multiples of 4 and 6 are 12, 24, 36, 48 and 60.  Divisibility by 2

 Hence, the numbers which are common among   rule:    All even numbers are divisible by 2. This means that numbers ending in 0, 2,
 the multiples of two or more numbers are called   Think Tank  Logical Thinking  4, 6 and 8 are divisible by 2.
 the common multiples.   There are 7 days in         Examples:  10, 256, 3498 are divisible by 2.

 Example: Find the common multiples of 2 and 5.   a week. Which of the
 following numbers of days will   Divisibility by 3
 Solution:   The multiples  of 2 are 2,  4,  6, 8,  10 ,   form an exact number of weeks?  rule:    If the  sum  of all  the  digits  of a number  is  divisible  by 3,  then  the  number

 12, 14, 16, 18,  20 , ...    7, 10, 13, 14, 20, 23, 28, 31  itself is divisible by 3.
         The multiples of 5 are 5,  10 , 15,  20 , 25, 30, 35, ...         Example:   In 24, 2 + 4 = 6 and 6 ÷ 3 = 2

         The common multiples of 2 and 5 are 10, 20, ...                 So, 24 is divisible by 3.


              Mathematics-4                                                                                          95
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