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Prime and composite numbers

2 videos
2 skills
Prime numbers have been studied by mathematicians and mystics for ages (seriously). They are both basic and mysterious. The more you explore them, the more you will realize that the universe is a fascinating place. This tutorial will introduce you to the magical world of prime numbers as well as their composite number brethren. Common Core Standard: 4.OA.B.4

Prime numbers

VIDEO 8:13 minutes
What does it mean to be a prime number? Let's progress though some whole numbers and ask ourselves if they meet the criteria. What is the criteria you ask? Watch.

Recognizing prime and composite numbers

VIDEO 4:40 minutes
Can you recognize the prime numbers in this group of numbers? Which are prime, composite, or neither?

Prime numbers

PRACTICE PROBLEMS

Composite numbers

PRACTICE PROBLEMS