A group of blondes walks into a bar, all excited and giggling. They order a round of drinks.

One of the blondes raises her glass and shouts excitedly, 51!! 51!! The other blondes echo. After they have finished their drinks, another round is ordered. Again, the blondes toast 51. This happens a few times.

Finally, the bartender speaks up. Excuse me, He says, But why do you ladies keep doing that? Well, Says one of the blondes, very bubbly, We got a puzzle, right? And it said 2-4 years on the box. We finished it in 51 days!!!!!