7th Grade Factors, Multiples and Primes Worksheet — Level 1 — Practice Set 3 — Answers
Answer sheet with worked solutions for the 7th Grade factors, multiples & primes worksheet.
Success TutoringWorksheetsAnswer sheet7th Grade · Mathematics · Factors, Multiples & Primes7th Grade Factors, Multiples and Primes Worksheet — Level 1 — Practice Set 3 — Answers
Part A: Factors
1.List all the factors of 25.
Answer: 1, 5, 25
2.List all the factors of 21.
Answer: 1, 3, 7, 21
3.List all the factors of 30.
Answer: 1, 2, 3, 5, 6, 10, 15, 30
4.List all the factors of 17.
Answer: 1, 17
Part B: Multiples
5.Write the first five multiples of 12.
Answer: 12, 24, 36, 48, 60
6.Write the first five multiples of 9.
Answer: 9, 18, 27, 36, 45
7.Write the first five multiples of 3.
Answer: 3, 6, 9, 12, 15
8.Write the first five multiples of 5.
Answer: 5, 10, 15, 20, 25
Part C: Prime or not?
9.15 is a prime number.
Answer: False
15 = 3 × 5, so it is composite.
10.39 is a prime number.
Answer: False
39 = 3 × 13, so it is composite.
11.28 is a prime number.
Answer: False
28 = 2 × 14, so it is composite.
12.17 is a prime number.
Answer: True
17 has only two factors: 1 and 17.
Marking tips
- Give credit for correct method even when the final answer slips — the working shows where the thinking went right.
- For open-ended tasks, use the success criteria as a checklist rather than looking for one "right" answer.
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