Who first used the comma and period to represent multiples of thousands and decimals and how did they do it?
Wednesday, September 9th, 2009I noticed that in the U.S., we use commas for thousands and periods for decimals and in Europe, it’s the inverse.
BCE, Aristophanes of Byzantium invented a system of single dots (distinctiones) that separated verses (colometry) and indicated the amount of breath needed to complete each fragment of text when reading aloud (not to comply with rules of grammar, which were not applied to punctuation marks until thousands of years later). The different lengths were signified by a dot at the bottom, middle, or top of the line. For a short passage (a komma), a media distinctio dot was placed mid-level ( ยท ). This is the origin of the concept of a comma, though the name came to be used for the mark itself instead of the clause it separated.
The mark used today is descended from a diagonal slash, or virgula suspensiva ( / ), used from the 13th to 17th centuries to represent a pause, notably by Aldus Manutius. In the 16th century, the virgule dropped to the bottom of the line and curved, turning into the shape used today.
ALSO SEE
http://en.wikipedia.org/wiki/Comma_(punctuation)#History
http://www.math.byu.edu/~jvogler/history_numbers.html
http://en.wikipedia.org/wiki/Names_of_numbers_in_English
~
Examples of how to convert a Decimal figure into a Fraction.
Your Best Friend playing Decimals (acoustic) on 6/5/09 at Hot Topic in Saginaw, MI
This video covers sovling multi-step equations that contain decimals. It includes three examples.
A mixed number is a number that contains both whole numbers and fractions. Change mixed numbers into decimals by creating a simple fraction and turning the fraction into a percentage with tips from a math teacher in this free video math lesson.
This video contains numerous examples of how to convert percents into fractions and decimals.
WEBSITE: http://www.teachertube.com ClanaMan explains what happens if the divisor the number on the outside is a decimal number.
Access full lesson containing this video at: http://www.yourteacher.com/prealgebra/roundingdecimals.php Students learn to round a decimal to a given place using the following steps. First, find the digit in the rounding place. Next, look at the digit to the right of the rounding place. If the digit to the right of the rounding place is less than 5, round down, which means that the digit in the rounding place stays the same, and all digits to the right of the place become zero. If the digit to the right of the rounding place is greater than 5, round up, which means add 1 to the digit in the rounding place, and all digits to the right of the rounding place become zero.