Number Sense · Unit 1
Animated explanations

See the math move.

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Prime numbers & factorization

Video + audio

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Three-step transcript

  1. Think about seven. It divides evenly by one and seven, and nothing else. So it's prime.
  2. Now try twelve. Two times six makes twelve, so it has more than two factors. That's composite.
  3. To factor sixty, keep splitting until every piece is prime: two times two times three times five.

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