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Dr. Math FAQ:
3D and higher
Browse Elementary History/Biography
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Selected answers to common questions:
About Roman numerals.
- History of Numerals and Counting: Bibliography [11/18/1996]
Where do I find information on different systems of measurements?
- History of Numerals and Symbols [06/22/1998]
Why and when did the change from Roman to Hindo-Arabic numerals occur?
What is the history of +, -, =, /, etc.?
- History of Odd and Even Numbers [02/12/2004]
Who invented the names 'odd' and 'even' numbers? When did they first
start being used?
- History of Radicals [2/6/1996]
Why do we call it square root when the symbol is called radical? I don't
understand the root part. Is it just its looks?
- History of Ratio and Proportion [12/28/2003]
Who discovered ratios and proportions? When did it happen?
- History of the Mile [08/25/2002]
Why are there 5,280 feet in a mile?
- History of the Order of Operations [11/22/2000]
Can you give me some facts and conjectures about when, where, and why the
order of operations was established?
- History of Writing Decimals and Number Lines [10/28/1998]
Why, on a number line, are the negative numbers are on the left? When you
deal with decimals, why are the whole numbers are on the left?
- History of Zero and Place Value [02/17/1999]
Where were zero and place value invented or discovered?
- How Pi Was Derived and Relates to Area of a Circle [03/04/1998]
Using inscribed and circumscribed polygons to derive Pi and circle area.
- How to Use a Chinese Abacus [06/24/2004]
An introduction to how the abacus works and examples of entering,
reading and adding numbers using it.
- Incan Quipus [09/30/1999]
Information on the colored ropes the Incas used for counting.
- Is K a Roman numeral? [07/19/1998]
A car ad shows 40K miles. Is this equal to a thousand?
- Large Roman Numerals [08/15/1997]
Could you please convert 5000, 1,000,000, and 5,000,000 into Roman
- Math on Africa [01/03/1997]
We're doing an interdisciplinary unit on Africa. My part is to do
something about math...
- Memory Aid for Roman Numerals [05/10/2000]
What number is XLIII? Do you have a way of remembering what letter equals
- Naming Large Numbers [06/05/2002]
In Rowlett's site for naming large numbers, he seems to take every
American prefix and bump its meaning by one to get the corresponding
Greek-based prefix. Why?
- Naming Small Numbers [07/29/2002]
Why were the names 'one', 'two', 'three', and so on, given to those
- The New Math [07/05/2000]
What is the "New Math?"
- Number Systems: Two Points of View [06/30/1998]
What are the number systems?
- Number Word Etymologies [05/03/2001]
Who made up the names for numbers?
- Numeral Systems and Representing Numbers [10/30/1998]
Can you tell me the different ways the number 8 is represented? For
example, what about different numeral systems?
- One Plus One [04/11/1997]
Are you sure that 1 plus 1 equals 2?
- Origins of Names of Ordinal and Cardinal Numbers [05/15/2002]
Which came first, ordinals or cardinals?
- Place Value and Roman Numerals [10/23/2001]
What is the importance of place value in relation to the value of a
- Questions About Math [11/26/1994]
Who invented math? Where does the word math come from?
- Questions from Second Graders [11/22/1994]
Where did the plus sign come from? Who invented numbers? How did they
come about? Where did the subtraction sign come from? Why does math have
patterns? Who was the first person (people) to use math? Where do the
Greater Than and Less Than signs come from?
- Roman Counting Instruments [04/24/1998]
Could you describe some of the early counting instruments developed by
- Roman Numeral [7/10/1996]
Why does the Roman numeral D stand for 500?
- The Second Millennium [11/29/1999]
Does the second millennium begin with the year 2000 or the year 2001? How
does this relate to the math of counting numbers and subtraction?
- Short History of Geometry [09/15/2001]
Were there any people who helped to develop geometry besides Euclid?
- The Welsh Vigesimal Number System [02/17/2003]
What can you tell me about the Welsh version of the Vigesimal Number
- What is a Sign? [04/21/2003]
Can you do anything in math without signs?
- When in Rome, Know Your Place — Less a Written Notation for It [01/27/2015]
An adult wonders how Romans could have developed their rules for subtraction
absent place value. Citing their use of the abacus, Doctor Peterson distinguishes
between operating with the concept and representing it.
- Where Did the Term "Math" Come From? [1/6/1995]
Where did the term math come from and what does the word math mean?
- Where Does Pi Come From? [11/04/1996]
If pi is a ratio of lengths that can be measured only so accurately, how
can we know the value of pi so exactly?
- Who Invented Decimals? [11/8/1994]
We are fifth grade students and one teacher. We would like to know who
- Who Invented Integers? [11/29/2001]
And when were integers invented?
- Who Invented Math? [2/15/1995]
An elementary student has some math history questions, as well as some
- Who Invented Multiplication? [6/7/1995]
Who made up multiplication?