Question

How does erics drawing show that 13 is a prime nunber?

Answer 1

1 to 100 of Prime Numbers
2,3,5,7,11,13,17,19,23,29,31,37,41,43,47,53,59,61,67,71,73,79,83,89,97.
The number 15 has divisors of 1,3,5,15 because:
15/1=15
15/3=5
15/5=3
15/15=1
So 15 is not a prime number.
The number 13 has only two divisors of 1,13.
13/1=13
13/13=1
So 13 is a prime number.