Prime Factor Tree

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Prime Factor Tree

• Discovering Prime Factors
• of Any Number

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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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Lets Choose a Number

• Lets use 36
• Choose any 2 factors lets use 9 and 4
• Now lets factor these numbers, too
• Next, arrange them from least to greatest
• Last, re-write as exponents

36
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Lets Try That Again!

• Lets use 36 again
• Choose any 2 factors lets use 3 and 12
• Now lets factor these numbers, too
• Oops, 6 is not prime - lets factor again!
• Next, arrange them from least to greatest
• Last, re-write as exponents
• Look, its the same answer!

36
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Lets Re-Cap

• Composite numbers are made up of factors
• In a Prime Factor Tree, the goal is to keep
  reducing each factor to its lowest possible prime
  factors
• When you have all the prime factors identified,
  re-arrange them from least to greatest and
  re-write them as exponents