Least Common Multiple - LCM

Today we worked on finding the the LCM of two numbers.  We reviewed what multiples are and many students were familiar with the strategy of finding the LCM by listing multiples of each number.  So for our example today, to find the LCM of 8 and 12 we listed multiples of each number and then found that the first one they had in common was 36.  

We also explored a new strategy that involves writing the prime factorization for each number using exponents.  Then you put the factors for each (with exponents) in a tic tac toe grid...all the twos( with exponents) go in one column, then the threes, etc.  Lastly, choose the largest number in each column (that's why the 2 cubed is circled) and multiply them together. This strategy was effective for students who enjoy working with exponents and are fluent with the fact that 2 cubed is 2 x 2 x 2.

As always, students can choose the method they prefer.  There are options for solving problems! Either way will direct you towards the answer!