Ancestry.com...worth it?

[The Q]

Since mine is purely British and Irish I don't require anything beyond that... well I thought it was, but Ancestry.com says I'm around 10% Scandinavian... who knew?

Since all parts of the UK and Ireland were at some point invaded by vikings or Normans, and large parts of Scotland were part of Scaninavian empires for many centuries, this is not at all unexpected.