I didn't count composite numbers like 6 or 10. I counted prime numbers;

half of numbers are not divisible by 2 (odd numbers)

1 3 5 7 9 11

as you see, 2/3 of them (odd numbers) are not divisible by 3 (1 5 7 11)

1/2 Ã— 2/3 = 1/3 of numbers are not divisible by 2 or 3

You aren't making your list long enough.

1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25, 27, 29, 31, 33, 35, 37, 39, 41, 43, 45, 47, 49 for example.

I count 15 primes out of 25 numbers. The ratio is closer to 1/2 than 1/3. This shows that your ratio of 2/3 is only an approximation. Part of the trouble here is that you have to have the

*whole* list of primes to do your ratios. Unfortunately, that list is infinite, so you are stuck with approximations.

-Dan