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11 Divisibility Rules and Prime Factorization Chapters 5.12 , Date _____
2 if the number is even3 if the sum of its digits is divisible by 35 if the last digit is 0 or 510 if the last digit is 0
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Finding FactorsA natural number is factored when it is written as the product of two or more natural numbers.
Natural numbers are the counting numbers: 1, 2, 3, 4, etc.
For instance, 32 can be factored as 4 8. The numbers 4 and 8 are factors of 32.
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How do we list all of the factors for 24?
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How do we list all of the factors for 24?
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List all of the factors for 36.
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List all of the factors for 36.
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List all of the factors for each number from least to greatest.
A. 15
B. 40
C. 45
D. 64
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List all of the factors for each number from least to greatest.
A. 15
B. 40
C. 45
D. 64
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A natural number is prime if it has exactly two factors, itself and 1.
Examples: 2, 3, 5, 7, 11, 13, ...
A natural number is composite if it has three or more factors.
Examples: 4, 6, 8, 9, 10, 12, ...
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Is the number prime or composite?
13 prime
26 composite
29 prime
1 neither
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Factor Trees
Use factor trees to factor a number until all of its factors are prime.
28
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Write the prime factorization of 40.
40
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Write the prime factorization of 40.
40
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Write the prime factorization of each number.
16 125
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Write the prime factorization of each number.
16 125
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Use a factor tree to write the prime factorization of each number.
E. 42 F. 60
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Use a factor tree to write the prime factorization of each number.
E. 42 F. 60
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Use a factor tree to write the prime factorization of each number.
G. 36 H. 75
I. 21 J. 200
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Use a factor tree to write the prime factorization of each number.
G. 36 H. 75
I. 21 J. 200