Prime numbers up to 12 are: 2, 3, 5, 7 and 11
Chat with our AI personalities
2/5 of the numbers from 1 to 20 are prime numbers
The prime numbers are: 2 3 5 7 11 and 13 so therefore as a fraction of 15 it is 6/15 or 2/5 simplified
2/5 are prime, 8/15 are composite (and 1/15 is neither).
The numbers 2, 3, 5, 7 and 11 are prime (including the boundaries).
The sum of any two prime numbers may or may not be prime. The sum of the two prime numbers 2 and 3 is the prime number 5, and the sum of the two prime numbers 5 and 7 is the composite number 12.