# Homework Help (Binary Arithmetic)

Hey guys, for my networking class we have learned some binary arithmatic. I’m fine with going from decimal (base 10) to binary (base 2), but the instructor also did a lesson on other systems (base 8 and base 16).

I found this extremely confusing. Does anybody know a good website that explains these processes better? I don’t need them right away because the test isn’t util the end of the semester, but any help is greatly appreciated.

Basically what I’m looking for is a detailed description how to go between these systems with examples. Something like 128(base 8)=X(base 16). However, those aren’t the only systems used.

Thanks ahead of time for any assistance.

If it helps, you can convert to base 10 and then reconvert.

128 (base 8) = 8x(8^0) + 2x(8^1) + 1x(8^2)
= 8 + 16 + 64
= 88
88 in base 16 is
88 - 5x(16^1) [Your tenth digit is <b>5</b>]
= 88 - 80
= 8 - 8(16^0) [Your ones digit is <b>8</b>]
= 0

So, 128(base8) to (base16) is 58.

Thanks guys! RC, that site if perfect!

Yeah. It’s saved my ass a few times already (my math teacher is brain dead).