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repeating decimals

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30 articles trouvés pour ce sujet.
Non-repeating decimals 2018-12-28
Grace pose la question :
What is non repeating decimal
Penny Nom lui répond.
The decimal form of a fraction 2018-01-12
Tom pose la question :
Prove that the decimal representation of the quotient of 2 integers must repeat (if it does not terminate).
Penny Nom 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.
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.
.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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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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