Download NNSO #2 Notes - Perry Local Schools

Name __________________________________________________ Period___________
NNSO #2 Notes
A. Classifying Numbers As Prime, Composite, or Neither
1. Prime = A whole number that has exactly 2 factors: 1 and itself
2. Composite = A whole number that has more than 2 factors.
3. Neither = There are only two numbers that can NOT be classified as prime or composite. Those two
numbers are: 0 and 1. We say they are NEITHER prime nor composite.
B. 100 Number Chart – Let’s find all of the PRIME numbers less than 100. Cross out any number that is
composite or neither. The numbers left over are PRIME numbers.
1. How many prime numbers are there less than 100? ________
2. How many even numbers are prime? ________ Explain why. _________________________________
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C. Prime Factorization – Writing a number as the product of prime numbers.
1. The tool that we use to write the prime factorization of a given number is called a FACTOR TREE
2. Factor trees might look completely different but still be totally CORRECT
3. Key points about factor trees:
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You can NEVER use 0 or 1 in a factor tree
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You may write any 2 factors of a number that multiplied together give you that number
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When you come to a PRIME factor, CIRCLE it
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Keep breaking numbers down until every branch ends in a PRIME number
4. Use the factor tree to write the PRIME FACTORIZATION of the given number. Write all of the prime
factors in order from least to greatest. Be sure to put multiplication signs (or dots) in between the
numbers.
5. Rewrite the prime factorization using EXPONENTS if possible. It will only be possible to use
exponents if the same prime factor appears more than one time in the prime factorization.
D. Examples - Write the prime factorization of each number by first drawing a factor tree. Remember, your
factor trees may look totally different from someone else’s tree, but still be correct. You will know that your
tree is okay if your prime factorization is correct. Rewrite the prime factorization using exponents if possible.
1. 56
2. 200
3. 75
4. 99
5. 45
6. 52
7. 100