Write down separately the prime and composite numbers less than 20

Question – Write down separately the prime and composite numbers less than 20.

Solution –

Prime numbers : Prime numbers are the numbers with exactly two factors i.e., 1 and itself.

Composite numbers : Composite numbers  has more than two factors

Prime numbers less than 20 are:
2, 3, 5, 7, 11, 13, 17, 19.

Composite numbers less than 20 are:
4, 6, 8, 9, 10, 12, 14, 15, 16, 18.

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