GMATPrep DS Question

[chatekar]

This question is from GMATPrep

If a wire 27 meters long is cut into three pieces of three different lengths, what is the length of the longest piece?

(1) The length of the longest piece is twice the length of the shortest piece
(2) The sum of the length of the two shorter pieces is 15 meters

OA is "Statement (2) alone is sufficient but statement (1) alone is not sufficient"

I think, statement (1) alone is also sufficient, as the only combination that satisfies the condition in statement (1) is 12, 9, 6 and it gives us the answer.

I'm confused why OA is different than what I think it should be, please advice

Thanks

[givemeanid]

The lengths can be 6.5,7.5,13. It doesn't say anywhere the lengths are integers. (1) is not sufficient.

[chatekar]

givemeanid,

Thanks.
I forgot the basics