CCSS.Math.Content.6.NS.B.4
The standard
Find the greatest common factor of two whole numbers less than or equal to 100 and the least common multiple of two whole numbers less than or equal to 12. Use the distributive property to express a sum of two whole numbers 1—100 with a common factor as a multiple of a sum of two whole numbers with no common factor.
Common Core State Standards for Mathematics · The Number System
What this standard means
Students need to find the greatest common factor for two numbers up to 100, the least common multiple for two numbers up to 12, and use those ideas to rewrite sums with the distributive property. They should be comfortable listing factors, listing multiples, and spotting the biggest shared factor or first shared multiple.
Mastery looks like choosing an efficient method, explaining why a factor is greatest or a multiple is least, and rewriting sums like 45 + 30 as 15(3 + 2). Students often mix up factors and multiples, stop too early when listing, or factor out a common number that is not the greatest common factor.
Ways to teach it
- Give pairs factor cards for 12, 18, 24, and 36, then have them build Venn diagrams to find greatest common factors.
- Ask students to explain in writing why 6 is the greatest common factor of 42 and 60, not just a common factor.
- Use an exit ticket with three items: find GCF of 28 and 70, LCM of 6 and 8, and rewrite 32 + 20.
- Connect to packing snack bags by asking how many identical bags can be made from 48 crackers and 36 grapes with none left over.
Plan a lesson for CCSS.Math.Content.6.NS.B.4
Generate a complete lesson plan aligned to this standard, with objectives, activities, and materials. Free, no account needed.
Related standards
- CCSS.Math.Content.4.OA.B.4
Find all factor pairs for a whole number in the range 1—100. Recognize that a whole number is a multiple of each of its factors. Determine whether a given whole...
- CCSS.Math.Content.5.NBT.B.6
Find whole-number quotients of whole numbers with up to four-digit dividends and two-digit divisors, using strategies based on place value, the properties of op...
- CCSS.Math.Content.6.NS.B
Compute fluently with multi-digit numbers and find common factors and multiples.
- CCSS.Math.Content.4.NBT.B.6
Find whole-number quotients and remainders with up to four-digit dividends and one-digit divisors, using strategies based on place value, the properties of oper...