Maria found the least common multiple of 6 and 15. Her work is shown below.

Multiples of 6: 6, 12, 18, 24, 30, 36, 42, 48, 54, 60, . . .
Multiples of 15: 15, 30, 45, 60, . . .

The least common multiple is 60.

What is Maria’s error?
Maria listed some values that were not multiples.
Maria listed factors of each number instead of multiples.
Maria should have multiplied 6 and 15 to find the least common multiple.
Maria selected a multiple that is not the least of the common multiples.

1 answer

Maria's error is that "Maria selected a multiple that is not the least of the common multiples." While 60 is indeed a common multiple of 6 and 15, it is not the least common multiple, as there is a smaller common multiple (30) that should have been identified first. Therefore, the correct answer is:

Maria selected a multiple that is not the least of the common multiples.