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





 We can see that 12 can be found by multiplying 1 and 12; 2 and 6; and 3 and 4.  Example 2: Find the factors of:  (a)  24    (b)  36
 That is, 12 = 1 × 12 = 12 × 1, 12 = 2 × 6 = 6 × 2, 12 = 3 × 4 = 4 × 3   Solution:  (a)  1 × 24  =  24  (b)  1 × 36  =  36
                                                                                                 Be Aware
 Thus, the numbers 1, 2, 3, 4, 6 and 12 are the factors of 12.  2 × 12  =  24  2 × 18  =  36  Stop the process when

 Hence, we can say that when we multiply two numbers to get a   3 × 4 = 12              3 × 8   = 24             3 × 12  =  36  the same factors are
 product, the numbers being multiplied are called factors.              4 × 6   = 24             4 × 9  =  36  there in a multiplication
                                                                                            fact.
 In other words, any number is a factor if it exactly divides the given   Factor   Product  6 × 6  =  36
 number, leaving no remainder.           Thus, the factors of 24 are     Thus, the factors of 36 are
 Example:   2 12  6  ;  3 12  4
 12  12                      1, 2, 3, 4, 6, 8, 12 and 24.            1, 2, 3, 4, 6, 9, 12, 18 and 36.
 0  0         Using Division

 So, 2, 6 and 3, 4 are the factors of 12.
              To find  the  factors of a number  using  division,  divide                  Think Tank
              the number by each of the possible counting numbers.
 Think Tank  Critical Thinking                                                           Can a number have only one
              Example 3: Find all the factors of 60.                                     factor? Which number is it?
 There are 24 cells in   Solution:  We divide 60 by all possible counting numbers.
 each rectangle. Find
 the multiplication            60 ÷ 1 =  60 ; 1 and 60 are factors of 60.           1  2  3  4  5  6  10  12  15  20  30  60
 fact for each. Then,
 list the factors            60 ÷ 2 =  30 ; 2 and 30 are factors of 60.
 of 24 using these            60 ÷ 3 = 20  ; 3 and 20 are factors of 60.
 multiplication facts.
                             60 ÷ 4 = 15 ; 4 and 15 are factors of 60.
                                                                                               Be Aware
                             60 ÷ 5 = 12 ; 5 and 12 are factors of 60.                  Continue the process of
 Finding the Factors of a Number           60 ÷ 6 = 10  ; 6 and 10 are factors of 60.   division till the quotient is

 The factors of a number can be found by either multiplication or division.  All possible divisions are being tried out.  larger than the divisor.

 Using Multiplication  Thus, 1, 2, 3, 4, 5, 6, 10, 12, 15, 20, 30 and 60 are factors of 60.

 To find  the  factors of a number  using  multiplication,  we look  for numbers whose   Example 4: Write all the factors of 30.
 product is the given number.  Solution:     30 ÷ 1 = 30             1 × 30  =  30

 Example 1: Find the factors of 48.              30 ÷ 2 = 15       or     2 × 15  =  30

 Solution:  1 × 48 =  48; 1 and 48 are factors               30 ÷ 3 = 10             3 × 10  =  30
 of 48.  1 2 3 4 6 8 12 16 24 48              30 ÷ 5 = 6              5 × 6  =  30
          2 × 24 =  48; 2 and 24 are factors            Thus, the factors of 30 are 1, 2, 3, 5, 6, 10, 15 and 30.
 of 48.

          3 × 16 = 48; 3 and 16 are factors of 48.  to Find out Whether one Number is a Factor of another

          4 × 12 = 48; 4 and 12 are factors of 48.  We know that for a number to be a factor of another number, it must exactly divide
          6 × 8 = 48; 6 and 8 are factors of 48.  the larger number without leaving any remainder.

          There are no more pairs of numbers whose product is 48.  Example 5: Check whether the first number is a factor of the second number.
          So, 1, 2, 3, 4, 6, 8, 12, 16, 24 and 48 are all factors of 48.  (a)  7, 80     (b)  12, 144


              Mathematics-4                                                                                          89
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