4, 6, 8, 9, 10, 12, 14, 15, 16, 18
They all have more than two factors.
There are more than ten composite numbers and what they have in common is that they all have more than two factors whereas prime numbers have only two factors which are themselves and one.
The numbers 4, 6, 8, 9, 10, 12, 14, 15, 16, 18 are the first ten composite numbers.
12
composite numbers from one to ten: 4, 6, 8, 9, 10
4 & 9
All even numbers greater than 2 are composite.
The numbers 4, 6, 8, 9, 10, 12, 14, 15, 16, 18 are the first ten composite numbers.
There are infinitely many composite numbers. There are, therefore, infinitely many subsets of ten such numbers. There are, therefore, infinitely many possible sums.
The only prime number in the 90s is 97. So out of ten numbers one is a prime number and the remaining nine numbers are composite numbers. So 90s comprises of both prime numbers and composite numbers.
2520
4, 6, 8, 9, 10, 12, 14, 15, 16, 18 because these are the first ten composite numbers.
4, 6, 8, 9, 10, 12, 14, 15, 16, 18 are the first ten composite numbers