Prime & composite numbers worksheets
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A prime number has exactly two factors, 1 and itself. A composite number has more, and 1 is neither because it has only one.
Just 4th grade. Print it here, or open the page for examples and teaching notes.
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4th grade Core grade
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Prime and composite worksheets ask fourth graders to classify numbers from 2 to 99 by counting their factors. Primes have exactly two factors; composites have more. Deciding takes a quick divisibility check with 2, 3, 5, and 7.
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