Two friends

Two friends met as a good man perished together for a beer. After recovering the most important topics (politics, women, football ...), one asks:
- And how many children do you have?
- I have three children.
- And how many years have you?
A friend already does not want to answer a direct question directly, and then he says:
- The product of their years equals the number 36, and the sum of the years is the number of beers we drink here today.
The second thing and say:
- That is not enough!
- You're right. The oldest has bigger ears!

Correct answer:

a =  2
b =  3
c =  6

Step-by-step explanation:

$$\begin{gathered} abc=36 \\ 36=2\cdot 2\cdot 3\cdot 3 \\ a<b<c \\ a=2 \end{gathered}$$

$b=3$

$$\begin{gathered} c=2\cdot 3=6 \\ x=a+b+c=2+3+6=11 \\ y=a\cdot b\cdot c=2\cdot 3\cdot 6=36 \\ c=6 \end{gathered}$$

Try another example