Five of the same kind

I could not resist on writing about numbers today, after my office mate broke the silence in our office saying "now is 11:11am on 11.11.11". That is quite a lot of ones in such short phrase.

Binary representation of 2011.

The current year, 2011, is quite interesting from a math point of view. First of all, we got four unusual dates:

• 1.1.11
• 1.11.11
• 11.1.11
• 11.11.11 (Today)

Another interesting topic: July of 2011 has exactly 5 Fridays, 5 Saturdays and 5 Sundays. This happens only every 823 years!!! No, of course not. Obviously it doesn't happen every year neither. Listing just a few past years: 2005, 1994, 1988, 1983,1977... Is it not enough for you? Then I can tell you, last October had 5 Saturdays, 5 Sundays and 5 Mondays and it has the same cycle. Now, does it look a bit more interesting? Some one would say "not that interesting anymore". Well, if you notice that in total 7 months with similar property in 2011, then I will also agree. But, if I say that none of them has 5 Wednesdays, 5 Thursdays and 5 Fridays. Now I got you!!! Moreover, the calendar of 2011 repeats every 6 or 11 years. Exactly the same, but don't get excited either, because 2111 is not going to be so. 

Now I promise something interesting! Let's do some math: take the last two digits of your birth year and add your age (for the current year), so the sum is always equal to 111. Don't you believe?

Example: Rodrigo was born in 1985 and he turned 26 on 2011. So

85 + 26 = 111

Hope you enjoy it and don't forget your homework!

Take care folks ;-)