Can anyone explain this please?

[Oakum Picker]

After sitting on my DNA test since last July, I finally 'bit the bullet' and sent it off last month, receiving the results last week. I have been following the various threads on here & am finding the same as everyone else, no trees, too small trees, no response etc.

I must admit the whole thing left me rather underwhelmed although I have been able to confirm several lines of research including a couple around 1800 hundred where I only had circumstantial evidence but had made an educated assumption which has now proved to be correct.

I have hundreds of questions but now to the point. One of my predicted 4th cousins with whom I share 40cm across 3 (still don't really understand what that means), has no tree but an unusual married name so I have traced her back & with some confidence can say that she is the g-gd of my g-gm's brother which in fact makes us 3rd cousins. So far so good.

When I check our ethnicity:
Me Her
73% England, Wales & Northwestern Europe 2%Great Britain
11% Germanic Europe 82%Europe West
8% Ireland and Scotland 9%Ireland/Scotland/Wales
6% Norway 1%Scandinavia
2% Sweden

How can that be?