Finding LCM by Listing Multiples
Finding the LCM by listing multiples is a Grade 6 math skill in Big Ideas Math Advanced 1, Chapter 1: Numerical Expressions and Factors. Students list the first several multiples of each number and identify the smallest multiple they share — the least common multiple (LCM) — which is used for adding fractions with unlike denominators and solving problems involving repeating events.
Key Concepts
To find the LCM by listing multiples: (1) List the first several multiples of each number; (2) Identify multiples that appear in all lists; (3) Select the smallest common multiple as the LCM.
Common Questions
How do you find the LCM by listing multiples?
List the multiples of each number (multiply by 1, 2, 3, 4...) and find the smallest number that appears in both lists. For example, multiples of 4: 4, 8, 12, 16... and multiples of 6: 6, 12, 18... The LCM is 12.
What is the LCM used for in Grade 6 math?
The least common multiple is used to find the least common denominator (LCD) when adding or subtracting fractions with unlike denominators. It is also used to solve problems about events that repeat on different schedules.
What is the difference between LCM and GCF?
LCM (least common multiple) is the smallest number divisible by both numbers — used for fraction denominators. GCF (greatest common factor) is the largest number that divides both numbers — used for simplifying fractions.
Where is finding LCM taught in Big Ideas Math Advanced 1?
Finding LCM by listing multiples is covered in Chapter 1: Numerical Expressions and Factors of Big Ideas Math Advanced 1, the Grade 6 math textbook.