# Decimal 8?

1. Nov 20, 2007

### The_Z_Factor

Hi everybody, I want to ask about this, and Im not exactly sure what 'type' of math this is, so I put it under general math..sorry if its not the correct place for it.

Anyways, about a year ago my cousin who went to Georgia Tech, was talking to me about math. I asked him what he thought the most complicated math was, and he says, "Well I think decimal 8 math is the hardest". I asked him what it was and he told me that its a number system or a way of doing math using decimals of 8 instead of 10 like our normal number system. He never took the class, he just said its harder than calculus.

So, what is this math? And what is it used for?

2. Nov 20, 2007

### Feldoh

Did he mean base-8? Decimal itself implies base-10 you can't have decimal 8 I don't think.

3. Nov 20, 2007

### The_Z_Factor

That must have been what he said then. It was at least a year ago so I dont exactly remember, but I do remember him mentioning that all the problems are based on decimals of 8 instead of 10. He might have said decimal to make it easier for me to understand, being that I most likely had no clue what he would have meant had he said "base". Thanks for correcting me though.

4. Nov 20, 2007

### Ben Niehoff

It sounds like he's talking about the octal number system, but there's nothing remotely hard about that. Octal represents numbers in powers of 8.

You may have heard about hexadecimal, which represents numbers in powers of 16. Hexadecimal is useful because it provides a concise way to talk about binary numbers, as it's easy to write down a hexadecimal number by just taking the binary number 4 bits at a time:

101101101111 binary is

Octal is also useful, because you can take the bits three at a time:

101101101111 binary is

5557 octal

Octal numbers are used in UNIX to set permissions with chmod, since each group might have read, write, or execute permissions (i.e., 3 bits).

5. Nov 21, 2007

### HallsofIvy

He was at Georgia Tech and said he thought "base 8" was the hardest math? He was putting you on!