# 11 Of The Coolest Mathematical Facts You Never Knew

1. There is an entire book explaining how 1+1=2 works and makes sense.
– MrPandaCzar

2. The guy that proved the existence of irrational numbers was murdered for his finding.
– rngisforfailures

3. There’s exactly 10! seconds in 6 weeks.

n! (pronounced n factorial) means n*(n-1)*(n-2)*(n-3)*….*2*1. So 10! = 10*9*8*7*6*5*4*3*2*1 = 3,628,800.
– Krissam

4. It’s impossible to comb all the hairs on a tennis ball in the same direction without creating a cowlick. [This is called the hairy ball theorem].
– Notsoace

5. The decimal fractions of seven are the same six recurring digits, in the same order, but starting from a different one each time.

1/7 = 0.142857142857…

2/7 = 0.285714285714…

3/7 = 0.428571428571…

4/7 = 0.571428571428…

5/7 = 0.714285714285…

6/7 = 0.857142857142…
– king_olaf_the_hairy

6. The Fibonacci sequence is encoded in the number 1/89:

1/89 = 0.01 + 0.001 + 0.0002 + 0.00003 + 0.000005 + 0.0000008 + 0.00000013 + 0.000000021 + 0.0000000034…
– Euerfeldi

7. The creators of Futurama actually had to create a new mathematical formula to solve the brain swapping issue they had. It’s called The Futurama Theorem
– Randomdude2846

8. If you put 23 people in a room, there’s over 50% chance that at least two of them have the same birthday.
– usthcd

9. The Banach–Tarski paradox: Given a solid ball, there exists a decomposition of the ball into a finite number of disjoint subsets, which can be put back together in a different way to yield two identical copies of the original ball.
-luckypech

10. There are different kinds of infinity, and some are larger than others.
– mightbethrownaway

11. 22/7 is closer to the actual value of pi than 3.14 is.
– JamesIgnatius27