Who Invented Decimals?
From: Anonymous Date: Tue, 08 Nov 1994 13:23:01 -0700 (MST) Subject: decimals Hi. This is Tara, Erin, and David. We are fifth grade students and one teacher. We would like to know who invented decimals. Thanks.
Date: Tue, 8 Nov 1994 16:38:58 +0900 From: Margaret Patterson Hi Tara, Erin, and David! Thanks for writing to us. This is an interesting question. It is hard to point to exactly one person who invented decimals since it is an idea that went through many notational changes and usage. Decimals were used in ancient China, medieval Arabia, and Renaissance Europe. In the 1500's researchers and mathematicians were using some form of decimals, but not until Simon Stevin of Bruges were they brought to the common people. He wanted to teach people, "how to perform with an ease, unheard of, all computations necessary between men by integers without fractions." He dealt with tenths, hundredths, and thousandths not as fractions such as 1 1 and 1, but rather as decimals. He wrote them differently, though. He would write the power of ten assumed to be a divisor after or above the each digit of the decimal, so the number 2.456 would be written as 2 (0) 4(1) 5(2) 6(3) where the parentheses indicate that a circle is drawn around the number, or (0) (1) (2) (3) 2 4 5 6 And he didn't use the words tenth, hundredth, etc. He used "prime", "second", "third", etc. In 1616, the notation we use today first appeared in a book called _Descriptio_ by John Napier (Scotland) using a decimal point to separate the whole number part from the decimal number part. The next year he proposed using a comma instead to separate the two parts. Even today, most parts of the world use the comma. If you want to read more about this and about Stevin's life, I got this information from _A History of Mathematics_ by Carl B. Boyer. -Margaret, Math Doctor on Call
Search the Dr. Math Library:
Ask Dr. MathTM
© 1994-2015 The Math Forum