Use and Meaning of 'And' in Naming DecimalsDate: 12/01/2004 at 20:11:12 From: Emily Subject: May you please tell me what the word "and" means in math? Dear Dr. Math, Can you please tell me what the word "and" means in the word form of a decimal number? I don't normally see it when it is not used for math! Date: 12/01/2004 at 23:21:59 From: Doctor Peterson Subject: Re: May you please tell me what the word "and" means in math? Hi, Emily. You're probably thinking of the fact that, at least when we read a number the way teachers commonly insist, "and" is used only between the whole number and the fractional part. For example, we would say "one hundred fifty-two" for "152", but "one AND fifty-two hundredths" for "1.52". Of course, in real life people don't always follow that rule; but it does make sense if you want to be careful in your speaking. But the "and" there really doesn't have any different meaning there than it usually does, to connect two things together, meaning more or less the same as "plus". What's more important is that by only using it at the decimal point, when it is NOT used you know there is NOT a decimal point there! The value of using "and" carefully shows up mostly in fractions. Note the distinction here: one hundred and three hundredths = 100 3/100 = 100.03 ----------- ---------------- one hundred three hundredths = 103/100 = 1.03 ----------------- Also, one hundred three-hundredths = 100/300 = 1/3 ! ---------------- See this page: Saying Numbers Out Loud http://mathforum.org/library/drmath/view/57225.html This page deals with the related issue of hyphens: Place Value and Similar Numbers http://mathforum.org/library/drmath/view/63862.html If you have any further questions, feel free to write back. - Doctor Peterson, The Math Forum http://mathforum.org/dr.math/ |
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