Prime Factors Worksheet Grade 3-07 - Free Printable

Let's solve each problem step by step:

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Problem 1: Which of the following number is not the factor of 15?

- Factors of 15: The numbers that divide 15 without leaving a remainder are 1, 3, 5, and 15.
- Options:
- a. 5 (Yes, it is a factor)
- b. 15 (Yes, it is a factor)
- c. 9 (No, it is not a factor)
- d. 3 (Yes, it is a factor)

Answer: c. 9

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Problem 2: Which of the following numbers are the factors of 24?

- Factors of 24: The numbers that divide 24 without leaving a remainder are 1, 2, 3, 4, 6, 8, 12, and 24.
- Options:
- a. 12 (Yes, it is a factor)
- b. 6 (Yes, it is a factor)
- c. 8 (Yes, it is a factor)
- d. all of these (All the given options are factors)

Answer: d. all of these

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Problem 3: Which of the following numbers are the factors of 16?

- Factors of 16: The numbers that divide 16 without leaving a remainder are 1, 2, 4, 8, and 16.
- Options:
- a. 4 (Yes, it is a factor)
- b. 8 (Yes, it is a factor)
- c. 1 (Yes, it is a factor)
- d. all of these (All the given options are factors)

Answer: d. all of these

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Problem 4: Which of the following number is not the factor of 8?

- Factors of 8: The numbers that divide 8 without leaving a remainder are 1, 2, 4, and 8.
- Options:
- a. 5 (No, it is not a factor)
- b. 2 (Yes, it is a factor)
- c. 4 (Yes, it is a factor)
- d. 1 (Yes, it is a factor)

Answer: a. 5

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Problem 5: What is the prime factorization of 120?

- Prime Factorization: Break down 120 into its prime factors.
- \( 120 \div 2 = 60 \)
- \( 60 \div 2 = 30 \)
- \( 30 \div 2 = 15 \)
- \( 15 \div 3 = 5 \)
- \( 5 \div 5 = 1 \)
- Prime factors: \( 2 \times 2 \times 2 \times 3 \times 5 \)

Answer: c. \( 2 \times 2 \times 2 \times 3 \times 5 \)

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Problem 6: What is the prime factorization of 56?

- Prime Factorization: Break down 56 into its prime factors.
- \( 56 \div 2 = 28 \)
- \( 28 \div 2 = 14 \)
- \( 14 \div 2 = 7 \)
- \( 7 \div 7 = 1 \)
- Prime factors: \( 2 \times 2 \times 2 \times 7 \)

Answer: c. \( 2 \times 2 \times 2 \times 7 \)

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Problem 7: The prime factors of 40 are

- Prime Factorization: Break down 40 into its prime factors.
- \( 40 \div 2 = 20 \)
- \( 20 \div 2 = 10 \)
- \( 10 \div 2 = 5 \)
- \( 5 \div 5 = 1 \)
- Prime factors: \( 2 \times 2 \times 2 \times 5 \)

Answer: c. \( 2 \times 2 \times 2 \times 5 \)

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Problem 8: _________ is the prime factorization of 50.

- Prime Factorization: Break down 50 into its prime factors.
- \( 50 \div 2 = 25 \)
- \( 25 \div 5 = 5 \)
- \( 5 \div 5 = 1 \)
- Prime factors: \( 2 \times 5 \times 5 \)

Answer: b. \( 2 \times 5 \times 5 \)

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Problem 9: \( 2^3 \times 5 \) is the same as

- Simplify \( 2^3 \times 5 \):
- \( 2^3 = 8 \)
- \( 2^3 \times 5 = 8 \times 5 = 40 \)
- Options:
- a. \( 2 \times 3 \times 5 \) (This equals 30, not 40)
- b. 30 (Not equal to 40)
- c. \( 2 \times 2 \times 2 \times 5 \) (This equals 40)
- d. \( 6 \times 5 \) (This equals 30, not 40)

Answer: c. \( 2 \times 2 \times 2 \times 5 \)

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Problem 10: The prime factorization of 45 is

- Prime Factorization: Break down 45 into its prime factors.
- \( 45 \div 3 = 15 \)
- \( 15 \div 3 = 5 \)
- \( 5 \div 5 = 1 \)
- Prime factors: \( 3 \times 3 \times 5 \) or \( 3^2 \times 5 \)

Answer: a. \( 3^2 \times 5 \)

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Final Answers:

1. c. 9
2. d. all of these
3. d. all of these
4. a. 5
5. c. \( 2 \times 2 \times 2 \times 3 \times 5 \)
6. c. \( 2 \times 2 \times 2 \times 7 \)
7. c. \( 2 \times 2 \times 2 \times 5 \)
8. b. \( 2 \times 5 \times 5 \)
9. c. \( 2 \times 2 \times 2 \times 5 \)
10. a. \( 3^2 \times 5 \)

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