Ok back
I see people didn't understand it. Well I must say I wasn't too confident about the wording myself, but I couldn't have said it in any easier way, I think.
Here is how it is
Nbb = People with blue eyes and blond hair
Nb1 = people with blue eyes
Nb2 = people with blond hair
N = the whole population
From what you get:
Nbb Nb2
------- > -------
Nb1 N
Which can be rearranged to
Nbb Nb1
-------- > --------
Nb2 N
which answers the question: Bigger.