Number Systems with Bases other than 10 |
Counting in Different Bases
Decimal (10)
Binary (2)
Octal (8)
Hex (16)
0
0
0
0
1
1
1
1
2
10
2
2
3
11
3
3
4
100
4
4
5
101
5
5
6
110
6
6
7
111
7
7
8
1000
10
8
9
1001
11
9
10
1010
12
A
11
1011
13
B
12
1100
14
C
13
1101
15
D
14
1110
16
E
15
1111
17
F
16
10000
20
10
17
10001
21
11
18
10010
22
12
19
10011
23
13
20
10100
24
14
Binary | Octal | Hexadecimal
Using different numbers bases "fell out" of the mathematics curriculum for a period of time as people felt that the base 10 was the only base used in everyday life. However, with the prevalence of technology and computers, being able to move easily in computations from one base system to another is almost as similar as in moving easily from speaking in one language to another.
We will focus on the three number bases used by computers: the binary, the octal, and hexadecimal, for: "Three numeration systems, binary, octal and hexadecimal, are used when dealing with the internal workings of computers. To be a knowledgeable, efficient programmer requires at least a rudimentary understanding of how they work and how they are interrelated."
Numeration Systems with tables
for binary, octal, and hexadecimal systems
http://www.macdonald.egate.net/CompSci/Pascal/hnumeration.html
The binary number base uses only 2 symbols: 0 and 1. The numbers are then:
Binary Number
Decimal Number
A base 2 number would be written in expanded form as:
Or converting the above number to decimal would be:
8 + 0 + 0 + 0 = 8To add two binary numbers, the following chart is true:
Binary Addition
+ 0
1
0
0
1
1
1
10
So, the two possibilities are:
A )OR
B)
which means:
each time "carrying" over the "1."
1
1
10
2
11
3
100
4
101
5
110
6
111
7
1000
8
1001
9
1010
10
1011
11
1100
12
1101
13
1110
14
1111
15
10000
16
10001
17
10010
18
10011
19
10100
20
The octal number base uses only 8 symbols: 0, 1, 2, 3, 4, 5, 6, and 7. The numbers are then:
Octal Number
Decimal Number
A base 8 number would be written in expanded form as:
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which would convert to decimal form as:
16 + 1 = 17
The octal addition chart is:
+ 0
1
2
3
4
5
6
7
------------------------------------------------------------------ 0
|
|
|
|
|
|
|
|
|
|0
1
2
3
4
5
6
7
1
1
2
3
4
5
6
7
10
2
2
3
4
5
6
7
10
11
3
3
4
5
6
7
10
11
12
4
4
5
6
7
10
11
12
13
5
5
6
7
10
11
12
13
14
6
6
7
10
11
12
13
14
15
7
7
10
11
12
13
14
15
16
Using the above table:
Check if your calculator offers the option of different bases. If it does not, then you can always use the calculator at:
Converting binary to octal to hexadecimal numbers http://www.terra.cc.oh.us/dlm270/session1.htm1
1
2
2
3
3
4
4
5
5
6
6
7
7
10
8
11
9
12
10
13
11
14
12
15
13
16
14
17
15
20
16
21
17
22
18
23
19
24
20
The hexadecimal number base uses 16 symbols. Since the decimal system only has 10 symbols,
6 more must be added. Those six are taken from the first letters of the alphabet,
so the symbols are: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E, and F. The numbers are then:
Hexadecimal Number
Decimal Number
A base 16 number would be written in expanded form as:
21 = (2 x 16) + ( 1 + 1)which would convert to decimal from as:
32 + 1 = 33
The hexadecimal system is most often seen
in designing web pages, where all color
combinations are represented
by hexadecimal numbers.
There are 216 cross platform colors
where each RGB color (red, green blue) is
expressed in a two digit code.For this page,
the background has color code ="FFFFFF"
which is white. Thus, this code is broken
in three position codes, since each color ranges
from 0 - 255. So white is made up of FF for red,
FF for green, and FF for blue.
FF = 255 which is the maximum amount of color
possible.The links on this page have color code 003366.
What would that color be?i. e. how much red?
how much green?
how much blue?1
1
2
2
3
3
4
4
5
5
6
6
7
7
8
8
9
9
A
10
B
11
C
12
D
13
E
14
F
15
10
16
11
17
12
18
13
19
14
20
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