Multiplying by Fractions and Decimals
Date: 5/31/96 at 2:49:5 From: Marie Langley Subject: math problem My granddaughter wants to know, "What number is 3\10 more than .025?" Thanks, Marie Langley
Date: 6/2/96 at 17:46:25 From: Doctor Brian Subject: Re: math problem Since your question involves both decimal and fractional representations for numbers, would you rather have the answer as a decimal or a fraction? I will address both forms: For decimals, we need to convert 3/10 to a decimal. Since your granddaughter seems to have some familiarity with decimals, she is probably aware that 0.3 is officially read as "three tenths," and therefore *is* the decimal representation for 3/10. At this point, we need simply to add the two decimals. Lining up the place values gives us: 0.3 0.025 ----- 0.325 For decimals, note that .025 may be read as "twenty-five thousandths." Therefore, the question is now 3/10 + 25/1000. Converting these to a common denominator of 1000 gives 300/1000 + 25/1000, which equals 325/1000. This fraction reduces to 13/40. (Don't worry, 13/40 is the fraction equivalent for .325.) -Doctor Brian, The Math Forum Check out our web site! http://mathforum.org/dr.math/
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