Converting Negative Mixed Numbers to Improper FractionsDate: 10/25/2006 at 00:22:58 From: Brenda Subject: Negative Mixed Numbers During the process of converting a negative mixed number into an improper fraction, I noticed that we do not pay any attention to the rules of adding negative and positive numbers. For example: -4 1/7 = -4 X 7 + 1 = -28 + 1 = -29/7, not -27/7 Why is this so? The rules of adding integers don't seem to apply. Shouldn't the final answer be -27/7? Date: 10/25/2006 at 00:38:54 From: Doctor Ian Subject: Re: Negative Mixed Numbers Hi Brenda, The rules apply just fine, once you realize that the mixed number a b/c is an abbreviation for (a + b/c) So -4 1/7 means -(4 + 1/7) = -(28/7 + 1/7) = -(29/7) = -29/7 It's exactly the same thing that happens with decimals, because decimals ARE mixed numbers: -3.29 = -3 29/100 = -(3 + 29/100) Does that make sense? Let me know if you need more help. - Doctor Ian, The Math Forum http://mathforum.org/dr.math/ |
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