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#1 2017-02-26 14:09:00

SuperLynx
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Registered: 2009-06-28
Posts: 335

Remainder in Fraction

I'm curious since their is a remainder for adding these fractions ? Considering 3x12 = 36 for the numerator, rather then 35.

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#2 2017-02-26 20:15:02

Bob
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Registered: 2010-06-20
Posts: 10,053

Re: Remainder in Fraction

hi SuperLynx

If you change each fraction into one with a denominator of 35 then you'll get a possible answer.

Bob


Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob smile

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#3 2017-02-27 11:44:43

SuperLynx
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Posts: 335

Re: Remainder in Fraction

For the first fraction you have to multiple the numerator and the dominator by what you got to get 35.  Before I go any further into adding the fraction by making the lowest common denominator; here is the fixed fraction.


I assume I put the result of 3x7=21 for the first fraction ?

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#4 2017-02-27 20:38:13

Bob
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Posts: 10,053

Re: Remainder in Fraction

hi Superlynx,

You are getting confused about how to add fractions.  Thirds and fifths are different fractions of a whole so it is necessary to convert both to a common denominator.  It's a bit like trying to add £ to Euros.  Unless you have both in the same currency, let's say $, you cannot add them correctly.  In your question the common denominator is /35 as this diagram shows:

jwJx4mU.gif

Hopefully you can see from the diagram that

Over to you to work out the other conversion.

Bob


Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob smile

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#5 2017-02-28 01:53:23

SuperLynx
Member
Registered: 2009-06-28
Posts: 335

Re: Remainder in Fraction

In other words, when you have found the lowest common denominator and you know the number which you used to find the lowest common denominator. You then simply multiple the numerator (and denominator) of the number you used to find the lowest common denominator for the first fraction, correct ?

Then you use the result of the answer for the numerator as in the case for the three over thirty-five for the first fraction ?

Last edited by SuperLynx (2017-02-28 16:11:54)

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#6 2017-02-28 07:01:24

Bob
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Posts: 10,053

Re: Remainder in Fraction

so

B


Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob smile

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#7 2017-02-28 16:13:33

SuperLynx
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Registered: 2009-06-28
Posts: 335

Re: Remainder in Fraction

You didn't tell me if my question on how to solve fractions when the denominator is different as in post #5 was correct ?

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#8 2017-02-28 21:07:54

Bob
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Re: Remainder in Fraction

hi SuperLynx,

I'm a bit confused about what you are asking. 

If the fraction sum is

Then a common denominator will be b x d.  It may not be the lowest, but that doesn't matter as you can always simplify later.

To get both fractions over this denominator you need to multiply the first, top and bottom, by d; and the second by b **.  So we have:

You can use this as a general formula.

** If you multiply the top and the bottom of any fraction by the same number, the value of the fraction is unchanged.  My diagram shows why this is true.

Hope that helps,

Bob


Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob smile

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#9 2017-03-01 05:52:20

SuperLynx
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Registered: 2009-06-28
Posts: 335

Re: Remainder in Fraction

Correct me if this is wrong, this is what I read;

You can find the lowest common denominator by finding what 3 and 7 will multiple by evenly ?


That leaves a remainder, since nothing will multiple by

to get
.  Therefore one can't use
as the lowest common denominator, one must use
, correct ?

Last edited by SuperLynx (2017-03-01 09:08:42)

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#10 2017-03-01 20:00:33

Bob
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Registered: 2010-06-20
Posts: 10,053

Re: Remainder in Fraction

No, not 21.  Look back to the diagram in post 4.

To show a fraction as part of a rectangle one must choose a suitable length and width for the rectangle.  The original question had sevenths and fifths so I knew that a rectangle 5 by 7 would be suitable.  I was able to split it into seven parts and also into five parts.  So the denominator to use is 35.

21 will not work because there is no whole number that you can use to change fifths into 21 parts.

My diagram shows that 3/7 is the same as 15/35 and that 3/5 is the same as 21/35.  I have now told you the complete answer so I don't think I can help in any other way with this problem.  I'll set you a new similar question if you want.

Bob


Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob smile

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#11 2017-03-02 12:13:12

SuperLynx
Member
Registered: 2009-06-28
Posts: 335

Re: Remainder in Fraction

What I don't understand is, there is no number that will multiple into

to get
besides
.  You have to use the same number you multiplied the denominator by with the numerator which is 5 that is what I was informed ?

Unless this is correct ?

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#12 2017-03-02 20:37:22

iamaditya
Member
From: Planet Mars
Registered: 2016-11-15
Posts: 821

Re: Remainder in Fraction

Hi Superlynx,
3/7+3/5=_/35+_/35
3/7+3/5=[(3*5)+(3*7)]/35=(15+21)/35=36/35
Now,_/35+_/35=(_+_)/35
Now since the value of the two nos. will be 36 so we can have 36/2= 18 possible answers. They are:
0 & 36
1 & 35
2 & 34
3 & 33
4 & 32
5 & 31
6 & 30
7 & 29
8 & 28
9 & 27
10 & 26
11 & 25
12 & 24
13 & 23
14 & 22
15 & 21
16 & 20
17 & 19
18 & 18
I think you're a little confused with the addition of fractions; hope this helps.
(Note: I've not learnt to use Latex format yet so I've written in normal format using the possible symbols in keyboard to denote fractions hope you understand and are not confused.)

Last edited by iamaditya (2017-03-02 20:37:40)


Practice makes a man perfect.
There is no substitute to hard work
All of us do not have equal talents but everybody has equal oppurtunities to build their talents.-APJ Abdul Kalam

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#13 2017-03-02 20:58:02

Bob
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Posts: 10,053

Re: Remainder in Fraction

SuperLynx wrote:

Unless this is correct ?

Yes.  Now change

by multiplying top and bottom by 7.

Bob


Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob smile

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#14 2017-03-02 21:00:25

Bob
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Registered: 2010-06-20
Posts: 10,053

Re: Remainder in Fraction


Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob smile

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#15 2017-03-02 21:43:27

iamaditya
Member
From: Planet Mars
Registered: 2016-11-15
Posts: 821

Re: Remainder in Fraction

Thanks Bob I'll try to learn as soon as possible.


Practice makes a man perfect.
There is no substitute to hard work
All of us do not have equal talents but everybody has equal oppurtunities to build their talents.-APJ Abdul Kalam

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#16 2017-03-02 23:38:09

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Remainder in Fraction

You can try the codecogs editor http://www.codecogs.com/latex/eqneditor.php?lang=en-en once you have learned how to do it by hand.


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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#17 2017-03-04 13:12:33

SuperLynx
Member
Registered: 2009-06-28
Posts: 335

Re: Remainder in Fraction

Therefore the answer is the following;

 
Good ?
smile

Last edited by SuperLynx (2017-03-04 13:13:08)

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#18 2017-03-04 23:18:00

Bob
Administrator
Registered: 2010-06-20
Posts: 10,053

Re: Remainder in Fraction

jwJx4mU.gif

Each little square is one 35th.  How many are shaded yellow?

you might find this page helpful:

http://www.mathsisfun.com/fractions_addition.html

Bob


Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob smile

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#19 2017-03-05 07:17:52

SuperLynx
Member
Registered: 2009-06-28
Posts: 335

Re: Remainder in Fraction

Without giving the answer.  Look at this fraction

There is nothing that will multiple into

to get
?

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#20 2017-03-05 20:17:30

Bob
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Registered: 2010-06-20
Posts: 10,053

Re: Remainder in Fraction

hi SuperLynx,

Yes, you're right.  I tried this two ways and got to the same answer; it is not a whole number.

method 1.  Start by adding the fractions using the usual rules.  This leads to something/96.  Simplify to something/24.

To change /24 into /60 you need to multiply top and bottom by 2.5  This gives a fraction with a denominator of 60.  Split off 5/60 and whatever numerator is left is the required answer.

method 2.  Change into /60 directly.  You can always make the denominator anything as follows:

You want 8 to become 60.  The multiplier that will do that is 60/8. 
You must multiply top and bottom by the same number so the new numerator is 7 x 60/8. 
As you will see this is not a whole number.

Continue to add the fractions with a denominator of 60.  Split off 5 of those for a first fraction and what's left is the required answer.

Bob


Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob smile

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#21 2017-03-06 04:53:27

SuperLynx
Member
Registered: 2009-06-28
Posts: 335

Re: Remainder in Fraction

method 1.  Start by adding the fractions using the usual rules.  This leads to something/96.  Simplify to something/24.

To change /24 into /60 you need to multiply top and bottom by 2.5  This gives a fraction with a denominator of 60.  Split off 5/60 and whatever numerator is left is the required answer.

Without giving the answer, I didn't understand your explanation ?

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#22 2017-03-06 07:11:49

Bob
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Registered: 2010-06-20
Posts: 10,053

Re: Remainder in Fraction

Ok, I'll make up a similar example and do it completely:

Step 1.  Add the fractions


Step 2. Now make this a fraction over 60


So ? = 43 and 1/3

Bob


Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob smile

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#23 2017-03-06 14:48:57

SuperLynx
Member
Registered: 2009-06-28
Posts: 335

Re: Remainder in Fraction

bob bundy wrote:

Ok, I'll make up a similar example and do it completely:

There is nothing which

or
will multiple by to get
? How do you get the numerator for the second fraction ? What do you do if you can multiple anything into the number to get the denominator ?

Last edited by SuperLynx (2017-03-06 15:06:00)

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#24 2017-03-06 21:22:08

Bob
Administrator
Registered: 2010-06-20
Posts: 10,053

Re: Remainder in Fraction

There is always a value that will change number x into number y (unless x=0).  Form the multiplier thus

So for 12 ---> 60  use 60/12 = 5 and for 9 ---> 60 use 60/9  = 20/3

Bob


Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob smile

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#25 2017-03-07 03:13:05

SuperLynx
Member
Registered: 2009-06-28
Posts: 335

Re: Remainder in Fraction

bob bundy wrote:

There is always a value that will change number x into number y (unless x=0).  Form the multiplier thus

So for 12 ---> 60  use 60/12 = 5 and for 9 ---> 60 use 60/9  = 20/3

Bob

I know I may be missing something.  You strictly took the

and instead of finding a number which multiples into it, to make
you did
?

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