#13 Probability

Below there are sixteen numbers. Assuming that any three of the numbers may be drawn at random, what are the chances that three numbers will be drawn whose sum equals six?

1 2 3 1
2 3 1 2
3 1 2 3
1 2 3 1

alright 1 week has passed,

Hint #1 the percentage (preferable answer form)

is below 50 and above 10

Hint #2  the answer ( in %) is between 30 and 20

I guess nobody likes math problems, anyway its over

 no one got it, that is except for my dad who gets 100 points

inquire within for the answer