Lesson 6.126.7 · 6.12 · 6.13 Catch-Up
Start hereWords, worked example, and sentence starters
Learning target I can show I am caught up on Lessons 6.7 · 6.12 · 6.13 by using each lesson's big idea in mixed practice.
Why This Matters Missed a lesson — or just want a refresher? This catch-up station reviews Lessons 6.7 · 6.12 · 6.13: 6.7 Find Factors and Multiples, 6.12 Least Common Multiple, 6.13 Prime Factorization. Work one example from each lesson, then prove you're caught up in the mixed practice.
Start hereWords for this lesson
Read each word before you begin. Say it out loud.
| Word | What it means | Example |
|---|---|---|
| FactorSpanish: Factor | A whole number that divides another number evenly, with no remainder. | Factors of 36: 1, 2, 3, 4, 6, 9, 12, 18, 36 |
| MultipleSpanish: Múltiplo | The result of multiplying a number by 1, 2, 3, and so on — where you land when you skip-count by it. | Multiples of 8: 8, 16, 24, 32, 40 … |
| Greatest common factor (GCF)Spanish: Máximo común divisor (MCD) | The largest number that is a factor of two or more numbers. It answers “how many equal groups can I make?” | 48 and 36 share 1, 2, 3, 4, 6, 12 → GCF = 12 |
| Least common multiple (LCM)Spanish: Mínimo común múltiplo (mcm) | The smallest number that is a multiple of two or more numbers. It answers “when will these line up again?” | 6, 12, 18, 24 and 8, 16, 24 → LCM = 24 |
| Factor pairSpanish: Par de factores | Two factors that multiply to make a number. In a word problem, one is the number of groups and the other is the size of each group. | 48 = 2 × 24, so 2 packs of 24 pencils |
| Prime factorizationSpanish: Descomposición en factores primos | Writing a number as a product of prime numbers, usually with a factor tree. Multiplying the primes two numbers share also gives the GCF. | 48 = 2×2×2×2×3, 36 = 2×2×3×3 → shared 2×2×3 = 12 |
How it worksWorked example
These numbers are not on your problems. The steps are. Follow them with your own numbers.
Find the GCF of 48 and 36.
- List the factors of each number: 48: 1, 2, 3, 4, 6, 8, 12, 16, 24, 48; 36: 1, 2, 3, 4, 6, 9, 12, 18, 36
- Circle the factors in both lists: 1, 2, 3, 4, 6, 12
- Choose the greatest one: GCF = 12
- The GCF of 48 and 36 is 12.
- Find the least common multiple (LCM) of 4 and 6.
- List the multiples of each number: 4, 8, 12, 16, 20, 24; 6, 12, 18, 24
- Circle the first number in both lists: 12
- The LCM of 4 and 6 is 12.
- Find the prime factorization of 60.
- Split 60 into two factors: 60 = 6 × 10
- Split each factor until all are prime: 6 = 2 × 3 → 10 = 2 × 5
- Write 60 as a product of primes: 60 = 2 × 2 × 3 × 5
- 60 = 2 × 2 × 3 × 5, or 2² × 3 × 5.
Now you trySame steps, your turn
The steps are the same as the worked example. The numbers are yours. Do the work.
Find the GCF of 12 and 20.
Say it and write itSentence starters
Finish each sentence out loud with a partner. Then use them in your writing.
- I know is prime because its only factors are and . I know is composite because it has factors like .
Word bank FactorMultipleGreatest common factor (GCF)Least common multiple (LCM)Factor pairPrime factorizationprimecompositefactorsdivisibletwo factorsmore than two
Watch out!A common mistake
A common mistake in Prime Factorization is stopping the factor tree too soon
Lesson 6.126.7 · 6.12 · 6.13 Catch-Up
Catch-UpSkill bridge
Learning target I can show I am caught up on Lessons 6.7 · 6.12 · 6.13 by using each lesson's big idea in mixed practice.
Why This Matters Missed a lesson — or just want a refresher? This catch-up station reviews Lessons 6.7 · 6.12 · 6.13: 6.7 Find Factors and Multiples, 6.12 Least Common Multiple, 6.13 Prime Factorization. Work one example from each lesson, then prove you're caught up in the mixed practice.
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1Complete each step, then write the final answer.
Find the GCF of 15 and 25.
Show your workHint List the factors of 15 and of 25.
Final answer: -
2Complete each step, then write the final answer.
Find the LCM of 3 and 4.
Show your workHint Skip-count by 3 and by 4. Find the first number in both lists.
Final answer: -
3Complete each step, then write the final answer.
Find the LCM of 2 and 3.
Show your workHint Skip count by 3: 3, 6. Which one is also a multiple of 2?
Final answer: -
4Complete each step, then write the final answer.
Find the LCM of 5 and 10.
Show your workHint Skip count by 10. Is 10 already a multiple of 5?
Final answer: -
5Complete each step, then write the final answer.
Fill in the blank: 20 = 2 × 2 × ___.
Show your workHint Start with 20 = 4 × 5. Then split 4.
Final answer: -
6Complete each step, then write the final answer.
Fill in the blank: 66 = 2 × 3 × ___.
Show your workHint Start with 66 = 6 × 11. Then split 6.
Final answer:
Explain your thinkingHow did you decide whether a number is prime or composite? What strategy did you use?
Sentence starter I know ___ is prime because its only factors are ___ and ___. I know ___ is composite because it has factors like ___.