what is the ratio or prime numbers to composite numbers in this list/10,11,2,13,14,15,16,1,7,18,19,20,21
It is impossible to list the infinite number of prime numbers and composite numbers.
That's an infinite list.
Look for a table of prime numbers. All the odd numbers that are NOT on this list are composite numbers.
That's an infinite list.
what is the ratio or prime numbers to composite numbers in this list/10,11,2,13,14,15,16,1,7,18,19,20,21
there are infinity odd composite numbers
The list of composite numbers is infinite.
That's an infinite list.
It is impossible to list the infinite number of prime numbers and composite numbers.
It is impossible to list the infinite number of composite odd numbers.
Please note that there are infinitely many prime numbers. An Internet search for "list of prime numbers" will quickly give you a list of prime numbers up to a certain point, for example here: http://en.wikipedia.org/wiki/List_of_prime_numbers Any integer greater than 1 that is not in the list of prime numbers is a composite number. (1 is considered neither a prime number, nor a composite number.)
That's an infinite list.
Look for a table of prime numbers. All the odd numbers that are NOT on this list are composite numbers.
18 prime numbers
The composite numbers in that list are 22 and 36 - you know they are composite, because they are even numbers. The other numbers are odd and prime.
That's an infinite list.