







Converting decimals to common fractions 
20180508 

From Ruth: what does the 0 represent in .018 versus the decimal .180? As in, changing these to fractions? Thank you. Answered by Penny Nom. 





The decimal form of a fraction 
20180112 

From Tom: Prove that the decimal representation of the quotient of 2 integers must repeat (if it does not terminate). Answered by Penny Nom. 





Changing a mixed number to a decimal 
20170923 

From karla: to change an improper fraction into a decimal 5 3/4 equals Answered by Penny Nom. 





Long division with decimals 
20170616 

From Kenneth: Hello:
Why is it recommended to move the decimal from a divisor when dividing so that the divisor is a whole number?
I know how to divide by moving the decimal from the divisor, but I cannot explain the reason.
I thank you for your reply. Answered by Penny Nom. 





Is 22/7 bigger or smaller than 3.14? 
20151106 

From Natalie: Is 22/7 bigger or smaller than 3.14? Answered by Harley Weston. 





The sum of two repeating decimals 
20151022 

From Kaitlin: Here is the question I am struggling with:
Is the sum of two repeating decimals always repeating decimal? Explain your answer and give an example.
I answered this question thinking that no you cannot but only when adding 0.9 repeating, but my professor said this was incorrect.
Thanks for the help!
Kaitlin Answered by Penny Nom. 





2.236... 
20151013 

From Ann: 2.236...
What is the most specific category of numbers does this fall into? Rational or Irrational? Does the .... mean that it repeats? Answered by Harley Weston. 





Repeated decimals 
20150509 

From Vir: Years ago I (re?)discovered 'cyclic division'. For example: if you arrange the number along a circle and put the number 142857 at the centre
all the numbers taken cyclically, starting with 1, are fully divisible by 37. Whatever the starting point of this number, it remains fully divisible by 37.
what is more, the number can be formed by taking the digits clockwise as well as anticlockwise..This I call "full cyclic divisibility". In many cases, only clockwise cyclic divisibility is possible. But I have not come across a case where ONLY anticlockwise divisibility occurs. Thus clockwise cyclic divisibility seems to be favoured. Could this be construed as a sign of chirality in mathematics?.. Answered by Chris Fisher. 





How do I make fractions into decimals? 
20140531 

From jay: Hi,
I wanted to know how do I make fractions into decimals example 1 3/8? Answered by Penny Nom. 





Decimals,fractions and percentages 
20140411 

From Frances: Ask an expert to find out their real life usage of your topic... that is the question.
meaning what is your real life usage of using decimals,fractions and percentages.
This is all part of my math assignment to ask an expert real life usage... so please
reply back as soon as possible Answered by Penny Nom. 





0.35 as a fraction 
20131128 

From Laura: How do you write 0.35 as a fraction or mixed number?
Laura Answered by Penny Nom. 





8 3/4 as a decimal 
20130515 

From Luisa: How to make 8 3/4 into a decimal Answered by Penny Nom. 





Converting a mixed number to a decimal 
20121110 

From Mahaveer: Convert mixed fraction to decimals: 4 2/6 Answered by Penny Nom. 





Converting a fraction to a decimal 
20121020 

From A Teacher: My students want an easy way to convert a fraction to a decimal, can I get one from you? Answered by Penny Nom. 





3.8 x 2.2 
20110818 

From Isaac: Question from isaac, a student: I am struggling in math & I need help on multiplying 3.8 x 2.2. Can you helpme Answered by Melanie Tyrer and Harley Weston. 





Write 3 1/5 in decimal form 
20110324 

From Stephenie: converting fractions????
3 1/5 into decimal??? Answered by Penny Nom. 





Decimal form 
20100908 

From Tracy: What is the decimal form of 0.14 x 10 the the first power? Answered by Penny Nom. 





How are decimals used in every day life? 
20100901 

From Keith: how are deciminal used in every day life Answered by Tyler Wood. 





Does 1= 0.9999....? 
20100407 

From Asia: Does 1= 0.9999....? There seems to be different opinions on this. Answered by Robert Dawson. 





Decimals and fractions 
20100316 

From fay: why do we use decimals in place of fractions in everyday life? Answered by Robert Dawson. 





Repeating Decimal 
20100314 

From Gerald: Find the 1987th digit in the decimal equivalent to 1785/9999 starting from decimal point. Can you give us a short but powerful technique in solving this problem? thanks so much.. Answered by Chris Fisher. 





Is 0.1234567891011.... periodic? 
20100223 

From Adriana: 0.1234567891011.......Is this fraction periodic ? Answered by Penny Nom. 





Working with decimals 
20100129 

From linda: Write 3 numbers that are between the following:
2.15 meters and
2.17 meters Answered by Harley Weston. 





Decimal equivalent 
20091213 

From Asia: In a forest,it rained 36 out of 90 days. What is the decimal equivalent of 30 out of 90 days Answered by Penny Nom. 





A rate of 67 per 1000 
20091110 

From ANTHNONY: if the rate is 67 per 1000 the fraction is 67/1000 how do I present the expanded form Answered by Penny Nom. 





Ordering numbers 
20090919 

From tattiana: how do you order these numbers from greatest to least .625,.75,.20, and .5 Answered by Penny Nom. 





Repeating decimal to fraction 
20090918 

From joan: how can i answer it easily to convert terminating decimal to fraction?
example of this is that, convert ...143143143... to fractional form Answered by Robert Dawson. 





Integers and decimals in day to day life 
20090629 

From mitichie: can you tell use of integers and decimals in our day to day life. Answered by Penny Nom. 





How many eighths are there in 1.25? 
20090506 

From Tamara: How many eighths are there in 1.25? Answered by Penny Nom. 





More on mills 
20090325 

From Kenneth: If I want to express 13 mills as a decimal part of $1.00, the answer
is $0.013. This amount is found by dividing 13 mills by 1000
mills/$1.00.
Can 13 mills be expressed as a decimal part of another amount instead
of $1.00? For example, express 13 mills as a decimal part of $1.50
or express 13 mills as a decimal part of $0.10. What would these
amounts be? Answered by Robert Dawson. 





How do I divide with a decimal is the divisor? 
20090315 

From Shelly: How do I divide with a decimal is the DIVISOR ( NOT divsor AND dividend.) ? Also, How do I know when to stop dividing?
P.s. please use long division Answered by Penny Nom. 





Express 13 mills as a decimal part of $1.00. 
20090313 

From Kenneth: Hello:
I read the following in an old business mathematics textbook:
"Express 13 mills as a decimal part of $1.00."
I can determine the answer as follows: There are 1000 mills in or per
$1.00. 13 mills divided by 1000 mills/$1.00 equals $0.013, the answer.
My question is as follows: What does "...as a decimal part of $1.00"
indicate or represent from "Express 13 mills as a decimal part of
$1.00."?
Is (a decimal part of $1.00) any decimal less than $1.00 with the decimal having a dollar sign
before it.
I thank you for your reply. Answered by Harley Weston. 





66 2/3% 
20090310 

From Traci: Please convert 66 2/3% into a decimal and a fraction Answered by Penny Nom. 





mutiplying decimals 
20090224 

From telly: how to do this sum0.24*0.398 Answered by Robert Dawson and Penny Nom. 





Decimals and fractions used in our daily lives 
20081204 

From josh: i have a projecct due friday and i need to know, how are decimals and
fractions used in our daily lives. i am having trouble coming up with
ideas. i need seven more that dont involve money or recipes. please
help me. Answered by Harley Weston. 





How do I compare fractions and decimals? 
20081118 

From Alexis: How do I compare fractions and decimals ? Answered by Penny Nom. 





A ratio to a decimal 
20081114 

From manny: Express 22 : 5 as a decimal. Round to the nearest hundredth Answered by Penny Nom. 





How do you work out 2/17 as a decimal? 
20081113 

From p: how do you work out 2/17 as a decimal? Answered by Penny Nom. 





A repeating decimal 
20081107 

From mike: what is 0.0028282828 recurring as a fraction? Answered by Penny Nom. 





The part before the repetend 
20081102 

From Puerto: Hello,
I teach mathematics in a bilingual programme using English. I have learned that the group of digits that repeat in a repeating decimal is called repetend but i need to know how are called the previous ones when the decimal is a delayedrepeating one. I mean, in 0.34555555 5 is the repetend, the period is one and...how are called 34?
Thanks in advance. Answered by Stephen La Rocque and Penny Nom. 





What are the equivalent to 0.68? 
20081028 

From clay: what are the equivalent to 0.68 ? Answered by Penny Nom. 





What is the exact value of pi? 
20080927 

From mahesh: what is the exact value of pi.
22/7 is accurate value of pi, if not then how can i find out the exact pi value. Answered by Harley Weston. 





0.99999.... 
20080923 

From Eve: Hi, i had a problem with change 0.99999... this recurring decimal to a fraction. I know the method, but the answer I got is 1 as you can see below.
Where have i done wrong? Answered by Harley Weston. 





Repeating fractions 
20080909 

From Juli: My teacher recently put my math class to the test...
We were deiscussing repeating fractions and she asked
us to find out what the bar over a repeating decimal is called. I found out
it was called the vinculum. But she also said to find out what the number
under the vinculum was called. I can't seem to find it anywhere. Answered by Penny Nom. 





How would put .12 with 2 repeating into a fraction? 
20080909 

From Savanna: How would put .12 with 2 repeating in fraction?
Savanna! Answered by Penny Nom. 





0.151515...=15/99 
20080908 

From Emma: This week, my Algebra teacher told us about the pattern between infinitely repeating
decimals and their corresponding fractions.
(ex. .2222222...= 2/9, .151515...=15/99, 456456456...=456/999, etc.)
I was just wondering the reason why this pattern occurs.
Is there a certain element that causes this pattern to occur?
Thanks
Emma Answered by Penny Nom. 





How do you write 92 tenths as a decimal? 
20080905 

From Miriam: How do you write 92 tenths as a decimal? Answered by Penny Nom. 





Long Division with Decimals 
20080828 

From Ghita: I need help with these 2 questions:
Find the quotients:
52.576 divided by 21
71.331 divided by 93
Ralph spent 5/9 of an hour mixing paints and 7/9 of an hour painting.How much time in all did Ralph spend on his project?
Thank you,Please answer soon Answered by Janice Cotcher. 





Convert Repeating Decimal into a Fraction 
20080825 

From Craig: Can you help me to convert:
0.444444 (repeating decimal  base 10) to base 9? Answered by Janice Cotcher. 





Nonterminating, nonrepeating decimals 
20080803 

From Peter: How do you take a random, nonterminating, nonrepeating decimal into a fraction? Answered by Stephen La Rocque. 





Sum of Digits 
20080724 

From Warren: If 100^2525 is written in decimal notation, what is the sum of digits? Answered by Penny Nom. 





A bijection from (0,1)x(0,1) to (0,1) 
20080720 

From Adam: I'm trying to prove that the function that takes the open square (0,1)x(0,1) to (0,1) is a bijection (and hence a continuum).
If we take an element (x,y) of (0,1)x(0,1) and represent (x,y) as (0.x1 x2 x3 x4..., 0.y1 y2 y3 y4...) aka x1 represents the tenths digit of x, x2 represents the hundredths, etc. Then we can define a function
f((x,y)) = 0.x1 y1 x2 y2 x3 y3... However, this is not a bijection. I hypothesize this is because you'd be unable to create the number 0.1 as x=0.1 and would have to be y=0, which contradicts the open interval (0,1) defined for y. We have been told though, if we create the same function, except that we "group" 9's with their next digit into a "block"
we can create a bijection. For example, if x=0.786923 and y=0.699213, then we define x1 to x3 as normal, but x4= 92, and x5=3. For y, we define y1 as normal, but y2=992, and y3 to y4 as normal. hence f((x,y)) = 0.7 6 8 992 6 1 92 3 3.
My questions are a) is my hypothesis on why the original function is not a bijection correct? b) why does the special blocking in the new function make a bijection? Answered by Victoria West. 





.9 repeating plus .2 repeating 
20080610 

From megan: How do you express the addition of .9 repeating plus .2 repeating? Answered by Penny Nom. 





How do you add decimals? 
20080605 

From nyheashiacurry: how do you add up decimals? Answered by Janice Cotcher. 





Converting a decimal to a fraction 
20080519 

From judy: please explain how to get from the decimal number .3437 to the fraction 11/32 Answered by Leeanne Boehm. 





Common fraction to decimal fraction 
20080401 

From chadwick: how do I turn 3/32 into a decimal Answered by Penny Nom. 





The decimal equivalent of a fraction 
20080324 

From Mario: What is the decimal equivalent of the fractions 5/8? Answered by Penny Nom. 





Repeating decimals 
20080310 

From Blaine: Is it possible to put a repeating decimal number into a calculator to solve a problem?
EX: Write 39.3939... as a fraction. Answered by Penny Nom. 





Multiplying decimal numbers 
20080205 

From alwyn: Why should when you Multiplying Decimal numbers is value becoming less and less? don't you think even decimal number is a quantity and in no chance when it multiplies its should become less or nil !!!
In fact all Multiplying and or adding the value will go up and only when you subtract and divide it should become less !! Answered by Stephen La Rocque and Penny Nom. 





Repeating decimals 
20080129 

From Malise: Write each repeating decimal using bar notation.
0.428571428... Answered by Penny Nom. 





Change a mixed fraction into a decimal 
20080123 

From Qiana: I need to know how to change a mixed fraction into a decimal. the mixed fraction is
9 1/2 Answered by Penny Nom. 





How many bags of cement will I need? 
20080115 

From James: I want to extend my front porshe more to the left atleast 14' 1" length wise and 5' 1" width wise with 4" thickness. Now i already decimalized in feet those inches, resulting with 14.08 length and 5.08width and 0.33 of thickness. I then Get my square feet of 71.53. And go on to cubic feet getting a 23.60 in cubic feet. Now i want to convert to cubic yards so i then divide 23.60 into 27 and get 0.87. Now my question is how would i use this to go and buy the necessary bags of cement knowing that a 94 lb. bag of cement is 1 cubic foot of bulk material. To fill 4 inch of thickness and 14' of length and 5 of width? Answered by Stephen La Rocque. 





1.2 as a fraction 
20080112 

From Confused: i have confused my brain and its driving me crazy i am trying to write 1.2 as a fraction but each time i do it i come out with a different number please help Answered by Penny Nom. 





Repeating decimals 
20071202 

From Jack: I've been working on an equation to support my theory of repeating decimals. Specifically the correlation between the 9 and 11 denominators. I wanted to know if there was already an equation to describe this correlation? Mine is x/11=.b repeating and b=9x, so if you use any single digit number for x (say 4) if 9 x 4 = 36 then 4/11 = .36363636... I just want to know if this theory already exists and if so, what is it called? Answered by Victoria West. 





How do you convert eleven fifteenths into a decimal? 
20071114 

From Lauren: How do you convert eleven fifteenths into a decimal? Answered by Penny Nom and Stephen La Rocque. 





A decimal to a fraction 
20071101 

From Lisa: i am trying to turn a decimal into a fraction. my example is to turn 10.5 into a fraction at its lowest form Answered by Penny Nom. 





For which values of k will k/240 be a terminating decimal? 
20071028 

From Clara: For which values of k will k/240 be a terminating decimal? Answered by Stephen La Rocque. 





0.24 1/2 
20070906 

From Kenneth: The fraction, 1/2, in 0.24 1/2 occupies the 1/100 place along with the 4.
If the fraction, 1/2, is changed to a decimal, as in 0.245, the last 5 in 0.245 occupies the 1/1000 place.
Why doesn't the 1/2 in the decimal 0.24 1/2 occupy the 1/1000 place (0.001) instead of the 1/100 place? Answered by Stephen La Rocque. 





Equivalent fractions 
20070831 

From Darlene: What is the equivalent decimal for 0.3 and 6.53 Answered by Penny Nom. 





Converting a repeating decimal to a common fraction 
20070822 

From isabelle: how do you turn 6.333... into a fraction in simplest form? Answered by Stephen La Rocque and Penny Nom. 





Division by decimals 
20070815 

From Brooklyn: I am studying for an exam, and I will not be able to use a calculator. I can not figure out how to do division is the number on the outside of the box is a decimal. Ex: 2/6.3=X Can you please help me figure this out? Answered by Penny Nom. 





Repeating decimals and rational numbers 
20070531 

From lil: Why are repeating decimals considered rational numbers? Answered by Penny Nom and Gabriel Potter. 





Fractions, decimals and profit 
20070529 

From fatima: how can i change a fraction into a decimal and how do i change a
decimal into a fraction................
anther question please what does making a profit have
to do with percentage change!!!!!! Answered by Penny Nom. 





Equivalent decimals 
20070316 

From megan: Write an equivalent decimal for 13.48. Answered by Stephen La Rocque and Penny Nom. 





A 15% tip 
20061206 

From Danielle: When she eats at a restaurant,Viviana like to leave a 15% tip,multiplying the price of the meal by 0.15. Franklin usually leaves a 20% tip,multiplying the price by 0.20.They both round up to the nearest $0.05. How much tip would Viviana leave for a $24.85 meal? Answered by Penny Nom. 





The real numbers with decimal representations consisting of all 1s. 
20061029 

From Ivessa: Determine if the following set is countable or uncountable : the real numbers with decimal representations consisting of all 1s. Answered by Steve La Rocque and Walter Whiteley. 





What is 1.7142857143 as a fraction? 
20061001 

From Lizzy: What is 1.7142857143 as a fraction? Answered by Stephen La Rocque and Penny Nom. 





Converting a decimal into a fraction 
20060906 

From Andres: How do i convert a decimal into a fraction? Answered by Penny Nom. 





The reciprocal of a decimal 
20060821 

From A student: I need help with finding the reciprocal of a decimal Answered by Leanne Boehm. 





Converting fractions to decimals 
20060725 

From Diane: HOW DO I CONVERT A FRACTION TO A DECIMAL? (E.G,. 8/14 to ? )
And HOW DO I DIVIDE A FRACTION (e.g., 1/14 divided by 3) and then convert that answer to a decimal? Answered by Penny Nom. 





Convert to decimal form 
20060112 

From A student: I would like to know the full answer on how to turn the fraction 3 3/8 into a decimal please. Answered by Penny Nom. 





Common fractions to decimals 
20051125 

From A student: how do u turn 8 over23 into a decimal and how do u turn 8 over 29 into a decimal Answered by Penny Nom. 





Isn't 1/3 written as a decimal .33? 
20050921 

From Lisa: Isn't 1/3 written as a decimal .33? My son informs me I'm wrong, but doesn't know the answer
Answered by Chris Fisher and Penny Nom. 





Equivalent fractions 
20050913 

From Cindy:
I am a parent and aunt of a 5th grader.
My nephew has asked me what the equivalent decimal is of 0.4. Does he change it to a fraction or just add a zero either before or after?
Answered by Chris Fisher and Harley Weston. 





0.999..., asymptotes and infinity 
20041217 

From Mike: My Name is Mike and I teach high school. I had a student ask me to explain why .9 repeating is equal to 1. Then he asked me about an asymptote, or why a parabola or any other curve for that matter can continually approach a value (like 1) and yet never attain a value of 1. He is thinking that these two should represent the same concept and yet they contradict each other. Do you have a solid explanation for him? Of by the way he is a 7th grader. Great little thinker!!!!! Answered by Claude Tardif and Harley Weston. 





Common fractions to decimals 
20040212 

From A parent: I'm trying to help my son work with turning fractions into decimals and this seems foreigh to me after 20 years of not being in school. Can you give me a few illustrations and/or examples of how to do that?? Answered by Penny Nom. 





Digits in the decimal expansion 
20040211 

From Leslie: In the decimal expansion of 1/17 what digit is in the 1997th place? Answered by Penny Nom. 





3/8 as a decimal 
20040113 

From A student: My Math Midterm is tommorow and I am stumped... how do you turn 1 and 3/8 into a decimal... I know the answer is 1.375 but I just copied down what the teacher wrote on the board.
Oh, and what are the three cases of percents? Answered by Penny Nom. 





0.810 and 0.801 
20031024 

From Ahmed:
could you please tell me what is the greatest decimal fraction formed of the digits 0, 1 , 8? Is it 0.810 or 0.801, please give me the reason of the answer in details and the references if it possible. Answered by Penny Nom. 





Why percentage? 
20030903 

From Vicky: My cousin aske me a question about the use of percentages and I'm not sure how to answer it. He wants to know why when there is a sale in a shop we use percentages and not fractions or decimals. Answered by Penny Nom. 





X.9999... and X+1 
20030823 

From David: I have read your answers to the questions on rational numbers, esp. 6.9999... = ? and still have a question: The simple algebraic stunt of converting repeating decimals to rational numbers seems to work for all numbers except X.999999.... where X is any integer. The fact that the method yields the integer X+1 in each case seems to violate the completeness axiom of the real numbers, namely that there is no space on the number line which does not have an number and conversely that every geometric point on the number line is associated with a unique real number. In the case of 3.999... for example, it seems that both the number 4 and the number 3.9999.... occupy the same point on the number line. How is this possible??? Answered by Penny Nom. 





Repeating decimals 
20030108 

From A student: If k=.9repeating, and 10k=9.9repeating then 10kk=9k, k=1 therefore .9repeating=1 and 1/3=.3repeating 3x1/3=.3repeatingx3, 3/3=.9repeating, therefore 1=.9repeating It would seem to me that .9repeating approaches one but never quite makes it. Can you clarify? Answered by Penny Nom. 





Decimals in everyday life 
20021124 

From Fritz: How do you use decimals in your every day life? Answered by Penny Nom. 





0.99999... 
20020926 

From Erica: Yesterday in my 8th grade math class we were being taught how to convert a Repeating Decimal into a fraction. Since I, for some odd reason, seem to understand math better than the rest of my classmates, i began to drown out my teachers explaination for the rule. While she was about half way through with explaining mixed decimals i came up with an unsolvable question. Like I said before, I understand how to turn a repeating decimal into a fraction, but how would I turn a repeating .9 into a fraction? We all know it would equal 9/9, but doesn't 9 over 9 also equal 1? Even though it comes very close to one, it never really equals one. I'm very confused about this and i would love it if you could clear this up for me. Answered by Penny Nom. 





The number of decimal places in 1 over a power of 2 
20020912 

From Allan: Does anyone notice that the maximum number of decimal place of the number 2 dividing 1 and its increment (4, 8, 16...etc) is the same as the power of number 2? eg. 2^{2}=4, thus the max number of decimal of ^{1}/_{4}=0.25 which is 2 decimal place and 2 is the number of power of 2 take 64 as example: 2^{6}=64, and take ^{1}/_{64}=0.015625 which has 6 decimal place (and is the power 6) Is there such a law in math? If yes, can you tell me what it is? Or is this my discovery? Answered by Paul Betts. 





1/8 in decimal form 
20020904 

From A student: explain how you put 1/8 in a decimal form Answered by Penny Nom. 





Common fractions to decimal fractions 
20020402 

From Natalie: My questions are: "how can I change 23/60 into a decimal. and give my answer to 2dp."?????????? 2nd question:for each of these pairs, which is bigger?
4/7 or 36%____________ 3/11or 0.29____________ 14/24 or 0.57___________ Answered by Penny Nom. 





The reciprocal of a decimal mixed number 
20020329 

From A student: How do I find the reciprocal of a decimal mixed number? Answered by Penny Nom. 





Multiplying decimals 
20020310 

From Kaitlin: I just recently had a test on multiplying decimals and I did not do really well on it. Only 5 kids out of 19 got a passing grade. My teacher says that she will give us a different test and we can take it again, but I'm still not sure of it. My teacher has taught me a lot and she had done a wonderful job of it but I'm just confused with where to put the decimals and stuff like that. I have a math practice workbook that I do for fun and they have nothing on decimals in it. I have checked on websites to try to find worksheets but I really couldn't find a good one. Can you please help me either give me some tips or clues or send me a worksheet. Answered by Penny Nom. 





The square root of 2 
20020305 

From Roger: Does two (2) have a square root or do the numbers just keep going? Are there any other numbers that behave like two when it comes to extracting the square root? Answered by Penny Nom. 





Fractions in lowest terms 
20011205 

From Thomas: how to change decimal to a fraction in the lowest terms .7 .65 .019 .0111 .225 .1225 .625 .25 .025 .26 .875 .5 .75 .750 .33 .09 .44 .15 .12 .90 .044 .2500 .95 .500 .02 .40 .125 .1276 .00009 .45 .125 .1276 .375 .975 .054 .0005 .20 .2 .0001 .85 .80 .9 .0007 9.8 10.17 25.75 48.4 80.35 19.64 276.20 31.042 18.1034 Answered by Penny Nom. 





0.999999=1? 
20010906 

From Catherine: Hi! My teacher told us that 0.9 repeating equals one. We discussed how this is true. But, I was wondering if there is a proof that this is true. If so what is this called? I was trying to find information, but, it's hard when you don't know the name. Answered by Walter Whiteley. 





Commas in numbers 
20010906 

From Mike: When did the Ontario Education system drop the use of commas in large numbers and replace with a space? Why? Answered by Walter Whiteley. 





Hours worked 
20010718 

From Carlos: I have a simple question:whats the formula to transform time into decimals? more exactly im working on a spreadsheet and i want to be able to type in for example hours worked: 11 11:30 pm and a formula would tell me 12.5 hours how do i do it? Answered by Patrick Maidorn. 





Repeating decimals 
20010421 

From Sarah: Hi, I'm working on a project for school. The theory I choose was "When turned into a fraction, a repeating decimal has a denometor that is a multiple of three." I have a couple of questions about this topic. My first question is, have you ever heard of this, and what can you tell me about it? My second question is, when I was testing this theory I came across .999... now, when this is a fraction it is 9/9 which is equal to one. The denometor is a multiple of 3, but it's a whole number. I don't understand how a decimal can be equal to a whole number since a decimal is a piece of a whole number. Please don't just show me a math problem, I don't want to see a math problem. I want to see an explanation of this theory and the decimal .999... Answered by Penny Nom. 





1 = 0.999... 
20010413 

From Joan: I have a middle grade math question for you. I would like to know why .9999... = 1 ? I can not use algebra to show this or the following: We agree that 2 = 2 and that 22 = 0, so
1.00000...... 0.99999.....  0.000000...... and 0.000... = 0 therefore 0.9 = 1 OR 1/3 = 0.333333 and 3 X 1/3 = 1, so if 3 X 0.333... = 0.999... then 0.999... = 1 My teacher says that I can not use the above example to show why this is true, and that I must use a couple different examples. He says that there are several other ways. Do you know any? I could really use the help because I can't think of any other ways to show this is true. Thanks for any help you can give. Answered by Penny Nom. 





Finite nonperiodical numbers 
20010327 

From Wouter: Is there anyone who knows the official name for decimal finite nonperiodical numbers such as 0.4 or 0.25 as opposite of numbers like 0.3333333... or 0.28571428571428...? Answered by Penny Nom. 





Cube roots on a calculator 
20010324 

From Will: Hi my name is Will.I have a question about the calculator TI83 Plus or the use of a scientific calculator. It is about using them to turn a cubed root to a decimal. When using that for a rational and irrational number. Rational numbers is a number that terminates or repeates. A irrational number goes on and on and uses ... (like pie). Like when you type the cube root of 8 it gives you 2, and that is a rational number. The squre root of 2 is 1.41421356... that is irrational. So why is it when you put the cube root of 16 in the calculator it says 2.5198421 that is rational it terminates at the ninth digit and my float is set for the tenth? But why when you do it by hand you get the 2 times the cube root of 2 and that is irrational? Why is that? Answered by Judi McDonald. 





The repetend in repeating decimals 
20010321 

From Sharon: What is the name for the bar over the repetend in repeating decimals? Also, what is the name of the long division "house"? Answered by Penny Nom. 





Converting percents to decimals 
20010301 

From Elliot: My math question is about Converting Percents to Decimals, here it is Convert 37 1/2 = ? Answered by Penny Nom. 





More repeating decimals 
20010117 

From Alan: I am neither a math teacher nor a student, but I hope you will consider my question anyway. I recently was discussing repeated decimals with a friend, and went on the web to find out more about a pattern was looking for years ago. In doing so I came upon your correspondence on repeating decimals. . . . Answered by Chris Fisher and Penny Nom. 





Multiplication of fractions 
20010108 

From Angela: Questions:
1. represent multiplication of fractions via an area model 2. describe why, not just how, to round decimals Answered by Penny Nom. 





Repeating decimal notation 
20001231 

From Clarende Duby: I have seen single repeating decimals for ex. 1/3 = 0.3 with the dot above the 3 to represent the repeating decimal. Then, there is the more common form of the bar over the top of the repeating number or group of numbers (called the period?). Which notation is correct? Answered by Penny Nom. 





Mixed Fractions 
20001209 

From Tim Finch: My son is having problems with mixed decimals and mixed fractions.. I am unable to find any information or examples on this subject so I can show him how to do it.. for example how do you make a mixed decimal or fraction out of 7/16 Answered by Penny Nom. 





Dividing with decimals 
20001115 

From Alex: I teach math and my class and I were discussing the dividing of decimals. I explained that if there is a decimal in the divisor, it needs to be moved and so does the decimal in the dividend. My question is why is it necessary to move the decimal point in the divisor before dividing? Answered by Penny Nom. 





Multiplying decimals 
20001016 

From Lily: I need help with mutiplying decimals (example) 2.28*0.48( * = times). Answered by Harley Weston. 





Repeating decimals 
20001006 

From Mary O'Sullivan: I understand that with repeating decimals (those with a pattern), the number of digits repeated is put into fraction form with the same number of 9's ex. 0.4444 = 4/9 0.145145145 = 145/999 How can I explain why this is so? Some inquisitive 8th graders are anxious to find out! Answered by Penny Nom and Walter Whiteley. 





Rational Numbers 
20000914 

From Josh Kuhar: How can you tell a number is rational? Answered by Harley Weston. 





Pi to 5 decimal places 
20000603 

From Emily: The question is find the value for pi to 5 decimal places???? Answered by Penny Nom. 





Rounding 
20000415 

From Tawana Brown: I was uncertain as to whether a number such as 85.25 rounding to the nearest tenth would be 85.3 or 85.2. I thought I had heard somewhere that if 5 is the last number that you don't round up. But I have also heard that anything 5 and above you do round up. It's been awhile since I've done rounding, so I need a refresher course. Answered by Walter Whiteley and Harley Weston. 





The sum of repeating decimals 
20000215 

From Caitlin Harris: Express 0.111... + 0.121212... + 0.123123123... as a repeating decimal and its equivalent fraction. Show work. Also, are there any extensions to this problem? In other words, are there any questions that we could ask that may be related to this problem? Answered by Penny Nom. 





Comma as decimal separator 
19991218 

From Franck Menuge: Could somebody tell me the origin of the use of a 'comma' as a decimal separator and of a 'dot' for thousands in the French numeric system, ex.1.234,56 Is it only used in France or in other european coutries? Why is it different in the UK? Answered by Patrick Maidorn and Penny Nom. 





Bases other than 10 
19991206 

From Garret Magin: We are doing a lesson on numbers of other bases than 10. We are working with binary, octal, and Hexadecimal. I was wondering what is used to represent number of different bases other then 16? Does it just continue on with the alphabet and if so what happens when you get to Z. It would be a help if you could answer this because it is really bugging me. And none of the math teachers at my school could let me know. Answered by Claude Tardif and Patrick Maidorn. 





Repeating decimals 
19991122 

From Andrew: Is 1.9 repeating the same as 2? Answered by Walter Whiteley. 





An equivalent decimal 
19991014 

From Cheryl Wendlandt: I have a question in my book that is one and five sixths and you are to put them in an equivalent decimal. I'm sick at home or I would be able to ask my instructor. I would appreciate any help. Answered by Penny Nom. 





Fractions, percents and decimals 
19990919 

From Sue Farr: My son is in 5th grade, and I can't seem to find any papers that have a simple explanation of how to convert decimals into fractions, percents into decimals, and viceversa. Answered by Harley Weston. 





Repeating decimals 
19990918 

From Kavoos Bybordi: I dont know how to change a reccuring decimal to a fraction please could you tell me the method. Answered by Penny Nom. 





Repeating decimals 
19990521 

From Stan: Hi, I am in Honors Math, and have confronted everyone, including teachers, about repeating decimals. What interests me is the number 0.9... and 1. Everyone says that since there is no number between 0.9...(repeating) and 1, that 0.9... = 1. However, isn't a repeating number a representation of a number, and not a real number? Let's look at it this way. 0.9 is close to 1. 0.99 is closer. 0.99999999999999 is even closer. so, 0.9... is a representation of it's closeness to 1. it's an active number... I don't understand how 0.9... is equal to 1. Please help me prove that 0.9... does NOT = 1. Answered by Penny Nom. 





The square root of two is never supposed to end 
19990306 

From a wondering student: i am algebra II and am in the 9th grade. today we were talking about rational and irrational numbers. When we were talking about square roots my friend and i were talking and we thought of something. if you have a square with sides of length one then the diagonal of the square is the square root of 2. Now the square root of two is never supposed to end. But the diagonal of the square ends so therefore doesn't the square root of 2 end. our math teacher did not really answer our question because it was not in the lesson plan and not to many people would see where we were coming from. the answer is really bugging me and i would like to have your input. Answered by Jack LeSage and Penny Nom. 





Dividing Decimals 
19990206 

From Melanie Campbell: i ugently need to know how to divide a decimal by a decimal eg:6.0 divided by 2.4 i need to show all working on a basic skills exam please help!!!! mel Answered by Jack LeSage. 





Turning Fractions into Decimals 
19990116 

From Lynn: How do you do it step by step Answered by Jack LeSage. 





Place Value 
19990105 

From Reg: I work in a Section 27 classroom with various grades. I am looking for assistance on how to deliver a lesson on place value:decimal numbers keeping in mind that they need to see it (visual) to comprehend. I am looking for grade 46 level. Answered by Jack LeSage. 





6.99999... = ? 
19981205 

From Tom: I have had a rather heated arguement with my students. Please settle this for me. Solve <,>, = 6.99999... __ 7 Thank you. Answered by Penny Nom. 





Terminating decimals 
19981116 

From Debra Karr: A college student studying elementary education asked me a question that I could not think of the correct answer. How can you look at a fraction and tell if is a terminating or non terminating decimal? Answered by Jack LeSage and Penny Nom. 





Fractions 
19981027 

From Jessica Braimoh: I have a problem that I just can't figure out!! Put into a fraction a) 1.157... b) 0.046... c) 0.032... d) 0.3234... Please show how you got the answer and how you came to it(step by step) Thanks Jessica Braimoh grade 9 Ontario Answered by Harley Weston. 





Repeating Decimals 
19981001 

From Chris Norton: Could you PLEASE give the formula to find out the number of digits in a repeating decimal before it repeats. I have been trying to get it for weeks from Math sites on the Internet. Can you please, please help me ? Chris Norton Answered by Chris Fisher and Penny Nom. 





Rational and Irrational Numbers 
19980919 

From Ri: I am trying to explain rational & irrational numbers to my niece who is grade 7 and am having difficulties. Could you please explain the difference between rational & irrational numbers. Thank you Ri Answered by Penny Nom. 





A Question About Pi. 
19970708 

From Mike Chan: I have read the section Repeating Decimals in your data base. It mention that 1/17 has at most only 16 repeating digits. But, why does "pi" have an infinite number of digits (and not repeating ). Answered by Penny Nom. 





Repeating Decimals 
19970124 

From Grant Reed: Is there a way to tell that the repeating decimal for 1/17 has no more than 16 repeating digits? Answered by Penny Nom. 





Repeating decimals 
19960909 

From Alice: What is the line called that is placed over the decimal to show that it is infinitely repeating? Answered by The Centralizer. 





Pronunciation 
19960305 

From Todd Stienhauser: Is 123.4 pronounced "one hundred and twenty three and four tenths"or "one hundred twenty three and four tenths"? Answered by Penny Nom. 

