How Do I Find The Binary, Oct, Hex Of This?! AH

[iGuest 3]

Alright. It's been going easy on me until I got to this one number while doing decimals. I came across (48-64) which would be -16 decimal. When I tried to do it in oct, I got a crazy amount! Same for hex! Binary, I got something like 11110000 using 2's Compliment I believe (1)11110000. Help please I can't seem to do anything about this to get the rest. I don't even know if the binary is correct too lol. I have until Wednesday to get this. And I still gotta get ASCII once I finish doing these 4.

[iGuest 3]

WAIT! No I didn't use 2's compliment. My fault. That was what I got from 00110000-01000000. So yeah, no 2's there. Still need help though of course >_<

[default1405241527 0]

Exists a program for linux/unix that converts to bin, to oct, to dec, tohex and to ascii...In really it is a kde application... khexeditor!try it...

[backfoot 0]

WAIT! No I didn't use 2's compliment. My fault. That was what I got from 00110000-01000000. So yeah, no 2's there. Still need help though of course >_<

You can also just use the widows calculator. It will convert from binary to dec to hex to oct.
Open the cal, go to "view" file menu and make sure "scientific" is selected then just enter the number in the entry box and hit the Hex/Bin radio buttons.