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CHAPTER-3: PLAYING WITH NUMBERS


               SUBTOPIC: Highest Common Factor

               LESSON NOTES-6


                     The Highest Common Factor (HCF) of two or more given numbers is the
                       highest (or greatest) of their common factors. It is also known as Greatest
                       Common Divisor (GCD).
                     There are three methods to find out the HCF of two or more given numbers.
                     Method -1: By using the repeated division method.

                       Method -2: By using Prime factorization method.
                       Method -3: By listing out the factors.

                     Method-1: By repeated division
                               Let us find out the HCF of 20,28, 36
























                     Method-2 Using Prime factorization
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