Prime Numbers

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Prime Numbers

• Some Simple Tips and Reminders

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Definitions

• Even Numbers Any number that can be divided by
  2
• Odd Numbers Any number that cannot be divided
  by 2
• Composite Number An integer that can be divided
  by at least one other number (a factor) other
  than itself

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Definitions

• Prime Number An integer whose only factors are
  1 and itself.
• Factor a number that can divide another number
  without a remainder.
• Prime Factors an expression of numbers that
  divides another integer without a remainder where
  all the factors are prime.

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What numbers are prime?

• Lets look at a number grid from 1 to 100 and see
  how they were discovered.

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Heres How You Do It
Take out the number 1 because it is a special
number
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Heres How You Do It
Take out the number 1 because it is a special
number
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Heres How You Do It
Take out numbers that have a composite factor of 2
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Heres How You Do It
Take out numbers that have a composite factor of 2
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Heres How You Do It
Take out numbers that have a composite factor of 3
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Heres How You Do It
Take out numbers that have a composite factor of 3
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Heres How You Do It
Take out numbers that have a composite factor of 5
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Heres How You Do It
Take out numbers that have a composite factor of 5
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Heres How You Do It
Take out numbers that have a composite factor of 7
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The PRIME Numbers!
Take out numbers that have a composite factor of 7
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How Do We Know They Are Prime?

• Composite numbers can be placed into varying
  types of rectangles
• Prime numbers cannot
• Lets look at that

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Composite Numbers
6
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Prime Numbers
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Thats It!

• A prime number cannot be divided by anything
  other than 1 and itself.