Is there some sort of specific meaning or rule in this domain that makes this problem mean something different to how it would be read at face value?
Without knowing anything extra, to me this reads:
1. Alan is young, round and kind
2. Alan is sometimes rough
3. Kind with rough skin are usually red
(Alan has not been stated to be in this category - unless "sometimes rough" implies "rough skin")
4. If red, then green
(As above, no information yet on whether Alan is red, so this gives no additional information about Alan)
5. Young, round and green are usually blue
(No information yet on whether Alan is green, so this gives no additional information about Alan)
6. Statement: Alan is not blue = ??
(No additional information since statements 1 & 2: Alan is young, round and kind, Alan is sometimes rough)
BTW - I have just numbered the statements in the order I used them, in case anyone wants to correct or discuss anything. This isn't the order they were given.
Edit: I am forgetting my predicate logic, and didn't recognise this. I think this example has more decoration (is more loosely worded) than I was ever used to. I now think "sometimes rough" and "rough skin" are intended to be interpreted as meaning the same thing.
That makes everything I wrote above this edit wrong. With the statement that Alan is rough, it is implied that Alan is usually blue