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              \\October 8, 2025 12:13 PM   Bharat Arora   P-9           Reader _________________________   Date: ___________________74





              Factor tree Method

                  Š Draw a factor tree and separate the prime factors at each step.
                  Š Continue factorisation till all the factors are prime.

              example 1: Prime factorise the following numbers using the factor tree method.
                    (  a)  24               (b)  36                  (c)  56                  (d)  108

                                                                                                   Be Aware
              Solution:     (a)     24                               (b)     36                 Since 1 is not prime,
                                                                                                number it is excluded
                                 2    ×   12                              2    ×   18          from any factor trees.


                                      2     ×    6                             2     ×     9


                                             2    ×   3                               3    ×   3
                                 24 = 2 × 2 × 2 × 3                       36 = 2 × 2 × 3 × 3

                            (c)     56                               (d)     108


                                 2    ×   28                              2   × 54
                                                                               2   × 27
                                      2     ×    14
                                                                                    3   × 9
                                             2    ×   7                                  3   × 3


                                 56 = 2 × 2 × 2 × 7                       108 = 2 × 2 × 3 × 3 × 3

              division Method

              To factorise a number using the division method, we follow these steps.
              Step 1: Divide the number by the smallest prime number which divides the number exactly.

              Step 2: Divide  the  quotient  again  by  the  smallest  prime  number.  If  the  quotient  is  not
              exactly divisible by the smallest prime number, divide it by the next smallest prime number.

              Step 3: Repeat the process till the quotient becomes 1.
              Step 4: Multiply all the prime factors.

              example 2:  Find the prime factors of the following numbers using the division method.

                    (  a)  44                        (b)  48                         (c)  132

              Solution:     (a)   2 44              (b) 2 48                       (c) 2 132
                                  2 22                   2 24                           2 66
                                 11 11                   2 12                           3 33
                                                         2 6
                                     1                   3 3                           11 11

                                                             1                              1

                                 44 = 2 × 2 × 11        48 = 2 × 2 × 2 × 2 × 3         132 = 2 × 2 × 3 × 11


              Mathematics-5                                                                                          6565
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