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CHAPTER-3: PLAYING WITH NUMBERS


               SUBTOPIC: Lowest Common Multiple

               LESSON NOTES-5


                     Lowest common multiple (LCM): The Lowest Common Multiple
                       (LCM) of two or more given numbers is the lowest (or smallest or least) of
                       their common multiples.
                     There are three methods to find out the LCM 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 multiples.

                     Method-1:By repeated division
                       Let us find the LCM of 20, 25 and 30.






















                       Steps to be followed:
                       (A) Divide by the least prime number which divides any one of the given

                       numbers. Here, it is 2. The numbers like 25 are not divisible by 2 so they are

                       written as such in the next row.
                       (B) Again divide by 2. Continue this till we have no multiples of 2.

                       (C) Divide by next prime number which is 3.
                       (D) Divide by next prime number which is 5.

                       (E) Again divide by 5.
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