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





                7.  A drum contains 220 litres of oil and another drum contains 336 litres of oil. Find the
                    largest capacity of a container that can exactly measure the oil from both drums.



                                                                                                             Critical Thinking
                     Challenge Question
                 A farmer plans to plant apple trees, orange trees, and mango
                 trees in rows such that each row contains only one type of

                 tree and has the same number of trees. The farmer has 132
                 apple trees, 176 orange trees, and 264 mango trees.
                 Find  the  greatest  number  of  trees  that  can  be  planted  in
                 each row. Determine how many rows will be needed in total.




              Lowest common muLtipLe (Lcm)

              Let us take any two numbers, say 4 and 6 and list the multiples of 4 and 6.

              Multiples of 4 are 4, 8,  12 , 16, 20,  24 , ...
              Multiples of 6 are 6,  12 , 18,  24 , ...

              Look at the given number line. It shows some multiples of 4 and 6.




                 0   1   2  3   4   5   6   7   8  9   10 11 12   13 14 15 16 17 18      19 20 21 22 23 24



              Common multiples of 4 and 6 are 12, 24, ...
                                                                                              Math Insight
              The lowest common multiple (LCM) of 4 and 6 is 12.                        When a number is a multiple

              Thus, the smallest number which is a multiple of two or more              of two or more numbers,
              given numbers is called the least common multiple (LCM).                  then it is called a common
              Methods of Finding lcM                                                    multiple of those numbers.

              We can find the LCM using any of the three methods:

                     (  i)  Common multiples method                  (ii)  Prime factorisation method
                   (  iii)  Division method

              common Multiples Method

              example 1: Find the LCM of 24 and 32 using the common multiples method.
              Solution:

                  Step 1:  Write some multiples of the number 24.
                             Multiples of 24 are 24, 48, 72,  96 , 120, 144, 168,  192, ...

                  Step 2:  Write some multiples of the number 32.
                             Multiples of 32 are 32, 64,  96 , 128, 160,  192, ...


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