Commas in Numbers
Date: 09/13/2001 at 21:44:17 From: LaToya Clayton Subject: Do commas change the value of a number Why are we taught in grade school to put the comma after the third digit in a large number? (9,876,543,210). Why not the fourth digit? (98,7654,3210). And does the comma really change the number value?
Date: 09/13/2001 at 23:28:50 From: Doctor Peterson Subject: Re: Do commas change the value of a number Hi, LaToya. The comma has no effect on the value of a number. All it does is make it easier for humans to read it. We put a comma every three digits to match the way we say numbers in English, by thousands. Your number reads naturally as 9 billion, 876 million, 543 thousand, 210 Divided every four digits, you would want to read it as something like 98 myrion, 7654 myriad, 3210 (I made up the word "myrion," but "myriad" really does mean "ten thousand".) The commas are purely for convenience. - Doctor Peterson, The Math Forum http://mathforum.org/dr.math/
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