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78 articles trouvés pour ce sujet.
Long division with decimals 2017-06-16
Kenneth pose la question :

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.

Penny Nom lui répond.
Is 22/7 bigger or smaller than 3.14? 2015-11-06
Natalie pose la question :
Is 22/7 bigger or smaller than 3.14?
Harley Weston lui répond.
The sum of two repeating decimals 2015-10-22
Kaitlin pose la question :
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!

Penny Nom lui répond.
Repeated decimals 2015-05-09
Vir pose la question :
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 anti-clockwise..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 anti-clockwise divisibility occurs. Thus clockwise cyclic divisibility seems to be favoured. Could this be construed as a sign of chirality in mathematics?..
Chris Fisher lui répond.
How do I make fractions into decimals? 2014-05-31
jay pose la question :
I wanted to know how do I make fractions into decimals example 1 3/8?

Penny Nom lui répond.
8 3/4 as a decimal 2013-05-15
Luisa pose la question :
How to make 8 3/4 into a decimal
Penny Nom lui répond.
3.8 x 2.2 2011-08-18
Isaac pose la question :
Question from isaac, a student: I am struggling in math & I need help on multiplying 3.8 x 2.2. Can you helpme
Melanie Tyrer and Harley Weston lui répond.
Write 3 1/5 in decimal form 2011-03-24
Stephenie pose la question :
converting fractions????

3 1/5 into decimal???

Penny Nom lui répond.
How are decimals used in every day life? 2010-09-01
Keith pose la question :
how are deciminal used in every day life
Tyler Wood lui répond.
Does 1= 0.9999....? 2010-04-07
Asia pose la question :
Does 1= 0.9999....? There seems to be different opinions on this.
Robert Dawson lui répond.
Decimals and fractions 2010-03-16
fay pose la question :
why do we use decimals in place of fractions in everyday life?
Robert Dawson lui répond.
Working with decimals 2010-01-29
linda pose la question :
Write 3 numbers that are between the following:

2.15 meters and
2.17 meters

Harley Weston lui répond.
Ordering numbers 2009-09-19
tattiana pose la question :
how do you order these numbers from greatest to least .625,.75,.20, and .5
Penny Nom lui répond.
Integers and decimals in day to day life 2009-06-29
mitichie pose la question :
can you tell use of integers and decimals in our day to day life.
Penny Nom lui répond.
How many eighths are there in 1.25? 2009-05-06
Tamara pose la question :
How many eighths are there in 1.25?
Penny Nom lui répond.
More on mills 2009-03-25
Kenneth pose la question :
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?

Robert Dawson lui répond.
mutiplying decimals 2009-02-24
telly pose la question :
how to do this sum0.24*0.398
Robert Dawson and Penny Nom lui répond.
Decimals and fractions used in our daily lives 2008-12-04
josh pose la question :
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.
Harley Weston lui répond.
How do I compare fractions and decimals? 2008-11-18
Alexis pose la question :
How do I compare fractions and decimals ?
Penny Nom lui répond.
A ratio to a decimal 2008-11-14
manny pose la question :
Express 22 : 5 as a decimal. Round to the nearest hundredth
Penny Nom lui répond.
What are the equivalent to 0.68? 2008-10-28
clay pose la question :
what are the equivalent to 0.68 ?
Penny Nom lui répond.
0.99999.... 2008-09-23
Eve pose la question :
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?

Harley Weston lui répond.
0.151515...=15/99 2008-09-08
Emma pose la question :
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?

Penny Nom lui répond.
Non-terminating, non-repeating decimals 2008-08-03
Peter pose la question :
How do you take a random, non-terminating, non-repeating decimal into a fraction?
Stephen La Rocque lui répond.
.9 repeating plus .2 repeating 2008-06-10
megan pose la question :
How do you express the addition of .9 repeating plus .2 repeating?
Penny Nom lui répond.
How do you add decimals? 2008-06-05
nyheashiacurry pose la question :
how do you add up decimals?
Janice Cotcher lui répond.
Repeating decimals 2008-03-10
Blaine pose la question :
Is it possible to put a repeating decimal number into a calculator to solve a problem?

EX: Write 39.3939... as a fraction.

Penny Nom lui répond.
Repeating decimals 2008-01-29
Malise pose la question :
Write each repeating decimal using bar notation. 0.428571428...
Penny Nom lui répond.
How many bags of cement will I need? 2008-01-15
James pose la question :
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?
Stephen La Rocque lui répond.
Repeating decimals 2007-12-02
Jack pose la question :
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?
Victoria West lui répond.
A decimal to a fraction 2007-11-01
Lisa pose la question :
i am trying to turn a decimal into a fraction. my example is to turn 10.5 into a fraction at its lowest form
Penny Nom lui répond.
0.24 1/2 2007-09-06
Kenneth pose la question :
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?

Stephen La Rocque lui répond.
Equivalent fractions 2007-08-31
Darlene pose la question :
What is the equivalent decimal for 0.3 and 6.53
Penny Nom lui répond.
Division by decimals 2007-08-15
Brooklyn pose la question :
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?
Penny Nom lui répond.
Repeating decimals and rational numbers 2007-05-31
lil pose la question :
Why are repeating decimals considered rational numbers?
Penny Nom and Gabriel Potter lui répond.
Fractions, decimals and profit 2007-05-29
fatima pose la question :
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!!!!!!

Penny Nom lui répond.
A 15% tip 2006-12-06
Danielle pose la question :
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?
Penny Nom lui répond.
Converting fractions to decimals 2006-07-25
Diane pose la question :

And HOW DO I DIVIDE A FRACTION (e.g., 1/14 divided by 3) and then convert that answer to a decimal?

Penny Nom lui répond.
Common fractions to decimals 2005-11-25
A student pose la question :
how do u turn 8 over23 into a decimal and how do u turn 8 over 29 into a decimal
Penny Nom lui répond.
Equivalent fractions 2005-09-13
Cindy pose la question :

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?

Chris Fisher and Harley Weston lui répond.
0.810 and 0.801 2003-10-24
Ahmed pose la question :

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.

Penny Nom lui répond.
Why percentage? 2003-09-03
Vicky pose la question :
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.
Penny Nom lui répond.
Repeating decimals 2003-01-08
A student pose la question :
If k=.9repeating, and 10k=9.9repeating then 10k-k=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?

Penny Nom lui répond.
Decimals in everyday life 2002-11-24
Fritz pose la question :
How do you use decimals in your every day life?
Penny Nom lui répond.
0.99999... 2002-09-26
Erica pose la question :
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.
Penny Nom lui répond.
The number of decimal places in 1 over a power of 2 2002-09-12
Allan pose la question :
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. 22=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: 26=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?

Paul Betts lui répond.
Common fractions to decimal fractions 2002-04-02
Natalie pose la question :
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___________

Penny Nom lui répond.
Multiplying decimals 2002-03-10
Kaitlin pose la question :
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.
Penny Nom lui répond.
Fractions in lowest terms 2001-12-05
Thomas pose la question :
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
Penny Nom lui répond.
Commas in numbers 2001-09-06
Mike pose la question :
When did the Ontario Education system drop the use of commas in large numbers and replace with a space? Why?
Walter Whiteley lui répond.
Repeating decimals 2001-04-21
Sarah pose la question :
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...
Penny Nom lui répond.
1 = 0.999... 2001-04-13
Joan pose la question :
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 2-2 = 0, so

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.

Penny Nom lui répond.
Finite non-periodical numbers 2001-03-27
Wouter pose la question :
Is there anyone who knows the official name for decimal finite non-periodical numbers such as 0.4 or 0.25 as opposite of numbers like 0.3333333... or 0.28571428571428...?
Penny Nom lui répond.
The repetend in repeating decimals 2001-03-21
Sharon pose la question :
What is the name for the bar over the repetend in repeating decimals? Also, what is the name of the long division "house"?
Penny Nom lui répond.
More repeating decimals 2001-01-17
Alan pose la question :
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.

Chris Fisher and Penny Nom lui répond.
Multiplication of fractions 2001-01-08
Angela pose la question :

1. represent multiplication of fractions via an area model

2. describe why, not just how, to round decimals

Penny Nom lui répond.
Mixed Fractions 2000-12-09
Tim Finch pose la question :
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
Penny Nom lui répond.
Dividing with decimals 2000-11-15
Alex pose la question :
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?
Penny Nom lui répond.
Multiplying decimals 2000-10-16
Lily pose la question :
I need help with mutiplying decimals (example) 2.28*0.48( * = times).
Harley Weston lui répond.
Repeating decimals 2000-10-06
Mary O'Sullivan pose la question :
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!
Penny Nom and Walter Whiteley lui répond.

Rational Numbers 2000-09-14
Josh Kuhar pose la question :
How can you tell a number is rational?
Harley Weston lui répond.
Rounding 2000-04-15
Tawana Brown pose la question :
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.
Walter Whiteley and Harley Weston lui répond.
The sum of repeating decimals 2000-02-15
Caitlin Harris pose la question :
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?
Penny Nom lui répond.
Repeating decimals 1999-11-22
Andrew pose la question :
Is 1.9 repeating the same as 2?
Walter Whiteley lui répond.
Fractions, percents and decimals 1999-09-19
Sue Farr pose la question :
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 vice-versa.
Harley Weston lui répond.
Repeating decimals 1999-09-18
Kavoos Bybordi pose la question :
I dont know how to change a reccuring decimal to a fraction please could you tell me the method.
Penny Nom lui répond.
Repeating decimals 1999-05-21
Stan pose la question :
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.
Penny Nom lui répond.
The square root of two is never supposed to end 1999-03-06
a wondering student pose la question :
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.
Jack LeSage and Penny Nom lui répond.
Dividing Decimals 1999-02-06
Melanie Campbell pose la question :
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!!!!

Jack LeSage lui répond.

Turning Fractions into Decimals 1999-01-16
Lynn pose la question :
How do you do it step by step
Jack LeSage lui répond.
Place Value 1999-01-05
Reg pose la question :
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 4-6 level.
Jack LeSage lui répond.
6.99999... = ? 1998-12-05
Tom pose la question :
I have had a rather heated arguement with my students. Please settle this for me.

Solve <,>, =
6.99999... __ 7

Thank you.
Penny Nom lui répond.

Terminating decimals 1998-11-16
Debra Karr pose la question :
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?
Jack LeSage and Penny Nom lui répond.
Fractions 1998-10-27
Jessica Braimoh pose la question :
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
Harley Weston lui répond.

Repeating Decimals 1998-10-01
Chris Norton pose la question :
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

Chris Fisher and Penny Nom lui répond.
Rational and Irrational Numbers 1998-09-19
Ri pose la question :
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
Penny Nom lui répond.

Repeating Decimals 1997-01-24
Grant Reed pose la question :
Is there a way to tell that the repeating decimal for 1/17 has no more than 16 repeating digits?
Penny Nom lui répond.
Repeating decimals 1996-09-09
Alice pose la question :
What is the line called that is placed over the decimal to show that it is infinitely repeating?
The Centralizer lui répond.



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