#### Answer

33

#### Work Step by Step

Use the factor tree to find the prime factorization for each number:
11 is already prime, so simply circle the 11. You can show an 11 and a 1 "branching" out from the top 11 just to show work, but it is an unnecessary step.
3 and 11 are factors of 33. Both are prime. So, the prime factorization of 33 is 3x11.
Use each prime number the greatest number of times it appears in either numbers' prime factorization.
3 appears the most (1 time) in 33 and 11 appears the same amount of times (1 time) in both 11 and 33.
Therefore, the LCM is 3x11 which equals 33.