All the numbers are composite except the ones in bold: 18 19 20 21 22 23 24 25.
It is 19 which is a prime number
wowo is it a composite number dang how did I not see that...
16 + 16 + 16 + 17 + 18 + 18 + 18 + 19 + 19 + 20 + 20 + 20 + 21 = 238
Mean (12, 18, 19, 20, 21) = 18
20
19. It is prime.
It is 19 which is a prime number
21
It would be impossible to list them all, since numbers go on forever, but here are some of them: 2 - Prime 3 - Prime 4 - Composite 5 - Prime 6 - Composite 7 - Prime 8 - Composite 9 - Composite 10 - Composite 11 - Prime 12 - Composite 13 - Prime 14 - Composite 15 - Composite 16 - Composite 17 - Prime 18 - Composite 19 - Prime 20 - Composite 21 - Composite 22 - Composite 23 - Prime 24 - Composite 25 - Composite 26 - Composite 27 - Composite 28 - Composite 29 - Prime 30 - Composite 31 - Prime 32 - Composite 33 - Composite 34 - Composite 35 - Composite 36 - Composite 37 - Prime 38 - Composite 39 - Composite 40 - Composite 41 - Prime 42 - Composite 43 - Prime 44 - Composite 45 - Composite 46 - Composite 47 - Prime 48 - Composite 49 - Composite 50 - Composite
It is composite.
wowo is it a composite number dang how did I not see that...
It's composite.
Prime numbers: 11, 13, 17, 19, 23, 29 Composite numbers: 10, 12, 14, 15, 16, 18, 20, 21, 22, 24, 25, 26, 27, 28, 30
The number 19 it is between 18 and 20 and is a Prime Number.
All of them except for 11, 13, 17 and 19 which are prime numbers
It is 1 because 19 is a prime number
15 is a composite number - it can be divided by 3 and 5. 11, 13, 17 and 19 are all prime numbers, not composite.