Numbering Systems and Place Values

Topics on this page:

Place Values, ones up to trillions
Place Values, tenths down to trillionths
Nicer place value chart, Trillions down to Quintillionths
American Numbering System
Googol and Googolplex
British Numbering System
About the author
Copyright Information

Place Values: ones up to trillions

A student asked me:
> What is the value of the digit 7 in 789,354,199,033?

To decide place values, we look at all the positions, starting at the decimal point, going right to left.

ones------------------------------------\
tens----------------------------------\  \
hundreds----------------------------\  \  \
                                     \  \  \
thousands------------------------\    \  \  \                   D
10 thousands-------------------\  \    \  \  \                  e
100 thousands----------------\  \  \    \  \  \                 c
                              \  \  \    \  \  \                i
millions------------------\    \  \  \    \  \  \               m
10 millions-------------\  \    \  \  \    \  \  \              a
100 millions----------\  \  \    \  \  \    \  \  \             l
                       \  \  \    \  \  \    \  \  \
billions-----------\    \  \  \    \  \  \    \  \  \           P
10 billions------\  \    \  \  \    \  \  \    \  \  \          o
100 billions---\  \  \    \  \  \    \  \  \    \  \  \         i
                \  \  \    \  \  \    \  \  \    \  \  \        n
trillions---\    \  \  \    \  \  \    \  \  \    \  \  \       t
10           \    \  \  \    \  \  \    \  \  \    \  \  \
trillions--\  \    \  \  \    \  \  \    \  \  \    \  \  \     |
100         \  \    \  \  \    \  \  \    \  \  \    \  \  \    |
trillions-\  \  \    \  \  \    \  \  \    \  \  \    \  \  \   v
           \  \  \    \  \  \    \  \  \    \  \  \    \  \  \  
          +--+--+--+ +--+--+--+ +--+--+--+ +--+--+--+ +--+--+--+
          |  |  |  | |  |  |  | |  |  |  | |  |  |  | |  |  |  |
          |  |  |  | |  |  |  | |  |  |  | |  |  |  | |  |  |  |*
          +--+--+--+,+--+--+--+,+--+--+--+,+--+--+--+,+--+--+--+

Write your number into the boxes above. Make sure the last digit of your number goes just before the decimal point in the chart.

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Place Values: tenths down to trillionths

What if you have positions after the decimal point? You count from tenths until you get to the position you are trying to determine the value of. Write the number you are trying to evaluate into the boxes below, starting at the decimal point on the left.

    decimal     +--+--+---+--+--+---+--+--+---+--+--+---+--+--+
     point      |  |  |   |  |  |   |  |  |   |  |  |   |  |  |
   -------->  * |  |  |   |  |  |   |  |  |   |  |  |   |  |  |
                +--+--+---+--+--+---+--+--+---+--+--+---+--+--+
                 /  /   /  /  /   /  /  /   /  /  /   /  /  /
tenths----------/  /   /  /  /   /  /  /   /  /  /   /  /  /
hundredths--------/   /  /  /   /  /  /   /  /  /   /  /  /
                     /  /  /   /  /  /   /  /  /   /  /  /
thousandths---------/  /  /   /  /  /   /  /  /   /  /  /
ten-thousandths-------/  /   /  /  /   /  /  /   /  /  /
hundred-thousandths-----/   /  /  /   /  /  /   /  /  /
                           /  /  /   /  /  /   /  /  /
millionths----------------/  /  /   /  /  /   /  /  /
ten-millionths--------------/  /   /  /  /   /  /  /
hundred-millionths------------/   /  /  /   /  /  /
                                 /  /  /   /  /  /
billionths----------------------/  /  /   /  /  /
ten-billionths--------------------/  /   /  /  /
hundred-billionths------------------/   /  /  /
                                       /  /  /
trillionths---------------------------/  /  /
ten-trillionths-------------------------/  /
hundred-trillionths-----------------------/

Place Values from Trillions down to Quintillionths

If you study this pattern, and the list of larger number names further down, you should be able to create your own chart going as high, and as small, as you'd like to go.

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American Numbering System

Here is the entire chart of all the number names (I know of) in the American Numbering System. Note that the British Numbering System does not match the American system after the millions. Thousands and Millions match, but then the British system has milliards, billions, billiards, trillions, trilliards, etc.

Since our numbering system is based on LATIN, for the number of sets of zeroes after 1,000. I have listed it by the number of ',000' sets after one thousand. Notice that BI=2 (bicycle), TRI=3 (tricycle), QUAD=4 (quadruplets). So, the latin numbers for 2 up to 100 are approximately represented in the names of the number groups.

number
of
0's  Name       samples of some of them
==--======---==================
    thousand    1,000
 1  million     1,000,000
 2  billion     1,000,000,000
 3  trillion    1,000,000,000,000
 4  quadrillion 1,000,000,000,000,000
 5  quintillion 1,000,000,000,000,000,000
 6  sextillion  1,000,000,000,000,000,000,000
 7  septillion  1,000,000,000,000,000,000,000,000
 8  octillion   1,000,000,000,000,000,000,000,000,000
 9  nonillion   1,000,000,000,000,000,000,000,000,000,000
10  decillion   1,000,000,000,000,000,000,000,000,000,000,000
11  undecillion 1,000,000,000,000,000,000,000,000,000,000,000,000
12  duodecillion       
13  tredecillion       The latin roots of the numbers show the
14  quattuordecillion  # of groups of 3-zeroes that follow 1000.
15  quindecillion      2=bi, 3=tri, 4=quad, 5=quin, 6=sex, 7=sept
16  sexdecillion       8=oct, 9=non, 10=decem, 20=vigin.
17  septendecillion
18  octodecillion      Names for groups 3 to 63 come from several
19  novemdecillion     sources, both encyclopedic and dictionary.
20  vigintillion
21  unvigintillion     Prefixes un-, duo-, tre-, quattuor, quin-,
22  duovigintillion     sex-, sept-, octo, and novem-, appear to
23  trevigintillion      modify TEN (decem) to make 11 to 19.
24  quattuorvigintillion
25  quinvigintillion       I followed the same pattern before
26  sexvigintillion        vigintillion to create 21 to 29 sets
27  septenvigintillion     of 000's after 1,000.
28  octovigintillion
29  novemvigintillion      decem=10, viginti=20, centi=100.
30  trigintillion
31  untrigintillion
32  duotrigintillion
33  tretrigintillion
34  quattuortrigintillion
35  quintrigintillion
36  sextrigintillion
37  septtrigintillion
38  octotrigintillion
39  novemtrigintillion
40  quardragintillion
41  unquardragintillion
42  duoquardragintillion
43  trequardragintillion
44  quattuorquardragintillion
45  quinquardragintillion
46  sexquardragintillion
47  septquardragintillion
48  octoquardragintillion
49  novemquardragintillion
50  quinquagintillion
51  unquinquagintillion
52  duoquinquagintillion
53  trequinquagintillion
54  quattuorquinquagintillion
55  quinquinquagintillion
56  sexquinquagintillion
57  septquinquagintillion
58  octoquinquagintillion
59  novemquinquagintillion
60  sexagintillion
61  unsexagintillion
62  duosexagintillion
63  tresexagintillion
64  quattuorsexagintillion
65  quinsexagintillion
66  sexsexagintillion
67  septsexagintillion
68  octosexagintillion
69  novemsexagintillion
70  septuagintillion
71  unseptuagintillion
72  duoseptuagintillion
73  treseptuagintillion
74  quattuorseptuagintillion
75  quinseptuagintillion
76  sexseptuagintillion
77  septseptuagintillion
78  octoseptuagintillion
79  novemseptuagintillion
80  octogintillion
81  unoctogintillion
82  duooctogintillion
83  treoctogintillion
84  quattuoroctogintillion
85  quinoctogintillion
86  sexoctogintillion
87  septoctogintillion
88  octooctogintillion
89  novemoctogintillion
90  nonagintillion
91  unnonagintillion
92  duononagintillion
93  trenonagintillion
94  quattuornonagintillion
95  quinnonagintillion
96  sexnonagintillion
97  septnonagintillion
98  octononagintillion
99  novemnonagintillion
100 centillion            100 sets of 000 after 1,000.
One GOOGOL is a ONE followed by 100 zeroes.
One GOOGOLPLEX is a ONE followed by one googol zeroes.
        (you can't write a googolplex, even in a million years)

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Googols and Googolplexes

What is a googol?

one googol is equal to ten, raised to the one hundredth power. It is written as a one followed by one hundred zeroes. This is a googol:

10,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000

What is a googolplex?

one "googolplex" is equal to ten raised to the googol power. If it were to be written out, it would be a one followed by one googol zeroes.

One googolplex equals 10 raised to the 10,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 power.

One googolplex is written as a one followed by 10,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 zeroes.

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British Numbering System

There is a fascinating article in Compton's Living Encyclopedia (AOL keyword: ENCYCLOPEDIA) that compares the American Numbering System with the British Numbering System. Once you get past eight zeroes, the names do not match. For example, a number followed by 9 zeroes is in the British "milliards" but the American "trillions".

In other words, the British Numbering System is completely different from the American Numbering System after the thousands and millions. Thousand and Million are the same, but then you see Milliard, Billion, Billiard, Trillion, Trilliard, etc.

TRIVIA QUESTION: If a "Billiard" is a one followed by 15 zeroes in the British System, then does this mean that is where we got the name of the game BILLIARDS, which is played with a cue ball and 15 numbered balls? If someone knows, please let me know.

Special thanks to Søren Gjellerup Christiansen in Denmark for this improvement on the paragraph above:

TRIVIA ANSWER:

I think it more likely that it has this name "billiard" because it is played with a stick (1) and 15 balls (0) - don't count the cue ball, it isn't numbered. Line them op and you get 1000000000000000 = one billiard.

I just find this more intuitive myself.

Of course, other people have written in to say that there is no relationship between the name of the game and the name of the number. But it is fun to think about.

number
of 0's Name samples of some of them ==--======---================== 3 thousand 1,000 6 million 1,000,000 9 milliard 1,000,000,000 12 billion 1,000,000,000,000 15 billiard 1,000,000,000,000,000 18 trillion 1,000,000,000,000,000,000 21 trilliard 1,000,000,000,000,000,000,000 24 quadrillion 1,000,000,000,000,000,000,000,000 27 quadrilliard 1,000,000,000,000,000,000,000,000,000 30 quintillion 1,000,000,000,000,000,000,000,000,000,000 33 quintilliard 1,000,000,000,000,000,000,000,000,000,000,000 36 sextillion 1,000,000,000,000,000,000,000,000,000,000,000,000 39 sextilliard 42 septillion NOTE that if you divide the # of zeroes by six, 45 septilliard you have the number that relates to the word of 48 octillion the group. 2=bi, 3=tri, 4=quad, 5=quin, 6=sex, 51 octilliard 7=sept, 8=oct, 9=non, 10=decem, 20=viginti. 54 nonillion 57 nonilliard the names for number groups 60 decillion (TEN) 3, 6, 9, 12, and every multiple 63 decilliard of 6 up to 120 came from 66 undecillion several sources, both dictionary 69 undecilliard and encyclopedic. 72 duodecillion 75 duodecilliard I followed the pattern of 78 tredecillion "million" to "milliard" to list 81 tredecilliard all other groups up to 123. 84 quattuordecillion 87 quattuordecilliard The prefixes un-, duo-, tre-, quattuor-, 90 quindecillion quin-, sex-, septen, octo-, and novem- 93 quindecilliard appear to modify the latin TEN (decem), 96 sexdecillion to make 11, 12, up to 19. 99 sexdecilliard 135 septendecillion 105 septendecilliard 108 octodecillion 111 octodecilliard 114 novemdecillion 117 novemdecilliard 120 vigintillion (TWENTY) 123 vigintilliard 126 unvigintillion I followed the prefix-pattern 129 unvigintilliard used before -decillion and 132 duovigintillion -decilliard to create the names 135 duovigintilliard for 126 to 177, 21 through 29 138 trevigintillion groups of six. 141 trevigintilliard 144 quattuorvigintillion 147 quattuorvigintilliard 150 quinvigintillion 153 quinvigintilliard 156 sexvigintillion 159 sexvigintilliard 162 septenvigintillion 165 septenvigintilliard 168 octovigintillion 171 octovigintilliard 174 novemvigintillion 177 novemvigintilliard you can figure out the names are for 180 through 597 zeroes by looking at the list for American Numbering System. 180, 186, 192 ...: Divide the number by 6, use that name. 183, 189, 195 ...: Change the name for 3 less. 600 centillion 603 centilliard? (absolute guess, not found in any source).

I don't know if the terms Googol and Googolplex are used in the British Numbering System. Since there were coined by American Mathematicians in 1929 and 1935, it is likely that they are not officially used in the U.K., but unofficially, I'm sure that some of them use it for fun.

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About the Author

You can find some of his puzzles on his web page at www.MAZES.com or at ftp:// www.mazes.com. More puzzles can be found at http://www.mazes.com/buymazes. John has written materials that can help people get ready for the Driver's License exam. You can find these materials at www.DriverExam.org or at ftp:// www.driverexam.org.

John is a computer programmer, consultant, web page designer, teacher, tutor and puzzle creator. John telecommutes throughout the world and is available to work for you. Please e-mail: John (at) Mazes.com.

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Copyright Information

If you use information from a source like this in a report, you should give proper credit, citing the author as a source. In other words, you must acknowledge where you found the information and who supplied it. This is a matter of professional courtesy. Here is an example of a footnote:

Footnote Example:
* John Knoderer, [webmaster(at)Mazes.com], "American Numbering System and Place Values," http://www.mazes.com/numberingsystem.html, 10 September 1997.

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