Friday, June 10, 2005

Why Not Base 11?

We all know how to count, right? 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10. That covers the sum of most people's fingers. But, 10 usually indicates an overflow, or carry, in whatever base you're dealing with. It's the effect of maxing out the digits in the base set.

For instance, in binary, you count 0, 1, 10.

In hexadecimal, you count 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E, F, 10.

When you count on your fingers, your 10th finger is not the carry--it's the last element in the set. So, counting on our fingers is actually using base 11, not base 10, since you don't carry the digit until you run out of fingers.

So, counting on your fingers should go like this: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, 10 (and 10 in this case is one more than when you run out of fingers).

This doesn't mean that I have 11 fingers, it means that when I hit 10 it shouldn't actually be called 10 because the carry/overflow hasn't occurred yet.