BINARY NUMBERS! help!?

Question

hi! i need help learning about binary numbers. when I was younger, I was showed how to get binary numbers in the form of a game. I really understood it, but now i totally forgot. I need to know how to change a whole number into a binary number, and how to change it back. I understand the concept, and I can add, but i have no idea how to subtract and multiply, and divide. please help!

Answer 1

ok, so
they are in the form
1,2,4,8,16,32,64,128,ect.
so 128 would be
00000001
129 is
10000001
51 would be
110011
1+2+16+32=51
basically, there is a way to make every number with those multiples.
to subtract 21 from 34
010001
-10101
you do it normally like in base 10, borrowing
you can learn this stuff from http://mathforum.org/library/drmath/view/55733.html

Answer 2

Remember:

2^0 = 1
2^1 = 10
2^2 = 100
2^3 = 1000
2^4 = 10000
2^5 = 100000
etc...

To do arithmetic functions in binary numbers, first do it in the decimal numbers, then convert.

Or better yet, use your Windows calculator!

Answer 3

000 = 0
001 = 1
010 = 2
011 = 3
100 = 4
101= 5
110 = 6
111 = 7

So if you see binary 110111011 this is octal 673
You covert to decimal by (8*6+7)*8 +3 = 443