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.
Start hereWords for this lesson
Read each word before you begin. Say it out loud.
| Word | What it means | Example |
|---|---|---|
| Find Factors and MultiplesSpanish: Hallar factores y múltiplos | Listing what divides a number evenly (its factors) and what it divides into evenly (its multiples), then finding what two numbers share. | GCF of 48 and 36 is 12 · LCM of 6 and 8 is 24 |
| 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 |
How it worksWorked example
These numbers are not on your problems. The steps are. Follow them with your own numbers.
Lesson 6.7 — Find Factors and Multiples: GCF = the biggest number that divides BOTH — use it to split into equal groups. LCM = the smallest number BOTH divide into — use it to find when cycles meet again.
- Lesson 6.12 — Least Common Multiple: The LCM is the FIRST number that shows up in both numbers' multiple lists.
- Lesson 6.13 — Prime Factorization: Keep breaking a number apart until every factor is a prime number you cannot split anymore.
Now you trySame steps, your turn
The steps are the same as the worked example. The numbers are yours. Do the work.
From 6.7: A factor tree breaks each number into primes. 48 = 2 × 2 × 2 × 2 × 3, and 36 = 2 × 2 × 3 × 3.
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 Find Factors and MultiplesFactorMultipleGreatest common factor (GCF)Least common multiple (LCM)Factor pairprimecompositefactorsdivisibletwo factorsmore than two
Watch outA common mistake
A common mistake in Prime Factorization is stopping the factor tree too soon — leaving a composite number like 4, 6, 8, or 9 in the final answer instead of continuing to split it. For example, writing 20 = 4 × 5 as the prime factorization (4 is composite) instead of finishing with 20 = 2 × 2 × 5. Before you submit, check every number in your final answer: if any factor can still be broken into smaller factors, the tree isn't finished yet.
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.
-
1Circle the letter of the best answer. Show how you know.
(Lesson 6.7) Which list shows all the factors of 12?
- A1, 2, 3, 4, 6, 12
- B1, 12
- C2, 3, 4, 6
- D12, 24, 36, 48
Hint Ask: what divides 12 with nothing left over?
Show your work -
2Circle the letter of the best answer. Show how you know.
(Lesson 6.7) Which list shows the first four multiples of 8?
- A1, 2, 4, 8
- B2, 4, 6, 8
- C8, 16, 24, 32
- D8, 9, 10, 11
Hint Skip-count by 8 out loud.
Show your work -
3Circle the letter of the best answer. Show how you know.
(Lesson 6.12) What is the LCM of 3 and 5?
- A3
- B5
- C15
- D30
Hint LCM is about MULTIPLES (counting UP by each number), not factors. You want the smallest number BOTH lists reach.
Show your work -
4Circle the letter of the best answer. Show how you know.
(Lesson 6.12) What is the LCM of 6 and 8?
- A6
- B14
- C24
- D48
Hint Careful: 6 + 8 is not a multiple of either number. You need a number that both 6 AND 8 divide into evenly.
Show your work -
5Circle the letter of the best answer. Show how you know.
(Lesson 6.13) Which of the following is a prime number?
- A9
- B15
- C17
- D21
Hint Re-read what 'prime' means: exactly two factors, 1 and itself. Any extra factor makes a number composite.
Show your work
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 ___.