Today is the birthday of our favorite puzzle maker, ErnÅ‘ Rubik, inventor of the Rubik’s Cube.
The Rubik’s Cube offers an interesting application of math. Check out this excerpt on the Cube from Answers.com:
A Rubik's Cube can have (8! × 38−1) × (12! × 212−1)/2 = 43,252,003,274,489,856,000 different positions (~4.3 × 1019), about 43 quintillion, but it is advertised only as having "billions" of positions, due to the general incomprehensibility of that number. Despite the vast number of positions, all cubes can be solved in 29 moves or fewer.
Rubik’s birthday and these combination figures remind me of the birthday problem: How many people must be in a room to have a 50% chance that any one of those people is the same age as any other? The answer: 23.
It’s interesting to me that with so many combinations of face configurations that the Rubik’s Cube can still be solved in 29 moves or less.
Of course, it’ll take me a few moves more than that, I’m sure. These instructions might help.
