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common denominator

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35 items are filed under this topic.
An equation with fractions 2016-03-09
From Ed:
7/10-___ +3/2=6/5
Answered by Penny Nom.
Adding mixed numbers 2013-11-20
From Kathy:
1 3/4 + 1 2/3= ?

5 1/2 - 2 5/6= ?

Answered by Penny Nom.
{(1+x)^1/3-1/3X(1+x)^-2/3}/(1+x)^2/3 2013-06-17
Answered by Penny Nom.
8 3/8 - 6 1/4 2011-03-21
From lenora:
explain an error pattern in each of the following. 8 3/8 - 6 1/4 = 2 2/4
Answered by Penny Nom.
1/a^2 + 1/b^2 2011-01-19
From robert:
If (a + b)^2 = 81 and ab = 18, find the value of 1/a^2 + 1/b^2 ?
Answered by Penny Nom.
x/200+x/400+x/600+x/800 2010-10-08
From Ashishthombre:
step by step LCM of x/200+x/400+x/600+x/800
Answered by Penny Nom.
Algebraic fractions 2010-04-22
From rory:
Answered by Robert Dawson and Harley Weston.
Least common denominator 2010-02-13
From Priscila:
3/8 + 4/5 + 7/3 + 9/10 = ?

Thank you for your assistance.


Answered by Penny Nom.
Combining fractions 2010-02-10
From Nick:
Combine the fractions

2m/t + 5/mt

Answered by Penny Nom.
Lowest common denominator 2008-05-31
From marlene:
cant get the common lowest denominator of 10,46,64
Answered by Janice Cotcher.
x/4 = 3 1/2 2008-05-30
From Kelsey:
How do you solve for "X" in the problem below?

--- = 3 1/2


Answered by Victoria West.
Ordering fractions 2007-11-15
From DEL:
Hi. I feel really stupid ! I'm a mature student and i have completely forgotten How to find out the order of fractions from largest to smallest. I Have been put this poser; 7/4...1/6....7/2 Can you please tell me what is the largest and lowest? Will be very grateful....thank you
Answered by Gabe Potter.
I need to order 3/11, 1/8, 2/9 from least to greatest 2007-10-19
From Andrew:
I need to order 3/11, 1/8, 2/9 in least to greatest.
Answered by Penny Nom.
Adding algebraic fractions 2007-08-14
From John:
Ive completely forgot anything to do with the subject mentioned, so my question is straight to the point..

I need to know how to do the following problem (Preferably do not give me an answer though) (k/3k-8) - (4/k+2)

Answered by Penny Nom.
Simplifying an algebraic fraction expression 2007-07-25
From Jessica:
How do I simplify b/(b2-25) + 5/(b+5) - 6/b?
Answered by Stephen La Rocque.
Common denominator 2007-01-10
From A parent:
what is the common denominator of 3/5, 2/7 and 4/8?
Answered by Stephen La Rocque.
Order the fractions from least to greatest 2007-01-04
From Justin:
I am a sixth grader, and I am having trouble with the last question in my homework assisgnment. 1/6, 2/5, 3/7, 3/5!
Answered by Stephen La Rocque and Penny Nom.
Least common denominator 2006-10-04
From Paulette:
Why is the LCD of 3/4 and 4/8 not the product of 4 and 8?
Answered by Penny Nom.
1/x + 1/y 2006-08-11
From Sonya:
what is 1/x+1/y = ? is it equal to 1/x+y or what?
Answered by Penny Nom.
The lowest denominator 2006-07-02
From Lisa:

What is the lowest denominator for the following numbers:

a) 26
b) 21
c) 47

Answered by Stephen La Rocque.
Adding fractions 2006-03-26
From Barbara:
I know that to subtract 1/4 from 2/3 I must find a common denom. Now the 2/3 becomes 8/12.....i understand the 12, but where does the 8 come from?
Answered by Penny Nom.
Adding improper fractions 2005-11-25
From Paula:
I would like a simple step by step explanation on how to add improper fractions.
Answered by Penny Nom.
Rational expressions 2005-11-15
From Zach:
I can solve easy problems such as (x/2)+3=2+(3x/4). That is easy because the Lowest Common Denominator is 4. But what really gets me stuck is a problem like this one. (6/x-2) = ( 21/(x-2)(x+2) )+ 1.
Answered by Penny Nom.
The least common denominator 2004-11-03
From A student:
Write the LCD for each pair of fractions.

13. 1/3,1/5

14. 2/7,1/4

15. 3/4,3/5

Answered by Penny Nom.
Rational expressions 2004-09-24
From A student:
In general, I understand rational expressions except when it comes to solving problems such as:

x+y/2x-y - 2x/y-2x or m-4/3m-4 + 3m+2/4-3m

I am confounded by the issue of having to find a common denominator. For example, if I tried to solve these problems by multiplying both denominators they would still be uncommon.

Answered by Claude Tardif.
Subtracting fractions 2004-05-11
From Filipe:

_5_ - __7__
6ab 8a

Answered by Penny Nom.
A/30 + B/105 = (7A + 2B)/x 2004-02-05
From Jim:
If A/30 + B/105 = (7A + 2B)/x and A, B, and x are integers greater than 1, what must x equal?
Answered by Penny Nom.
Adding fractions 2003-11-16
From Ken:
My name is Ken and I am taking my GED course for my High School and have not been in a class for 35 years. I am doing this for re-training. I am at the part about fractions. Here is an example that I am having trouble with.

1 3/7 + 4 2/3 + 11/21

They have no common denominators. Could you PLEASE help me. If you could send me a step by step explanation it would be greatly appreciated.

Answered by Penny Nom.
Subtracting rational expressions 2003-05-10
From Simone:
hi, i'm totally lost. i understand that you need to find a lowest common denominator to subtract two fractions (rational expressions) with different denominators. but what if the denominators are "x-1" and "x". is x the common denominator? if so what happens to the "-1"? do you know of any live online help i can get with the following:

3/(x-1) - (1-2x)/x

i've looked through my notes and have no examples that quite match that i can follow to get through it. please help!
Answered by Penny Nom.

The least common denominator 2003-01-21
From Brittan:
Hi there I need help! My name is Brittany and i am in the 6th grade.

I need help finding the least common denominator(LCD), and the book says Find the LCM of the denominators and i've done that and then it says write equivalent fractions,using the LCM as the least commonn denominator.The directions say Use the LCD to write each pair as like fractions. and the problem is 1/8 and 5/40. Could u explain how in the word u do this? Thanks a lot


Answered by Penny Nom.
Rational expressions 2002-10-03
From Ashley:
1/x(squared) + 5/xy
Answered by Penny Nom.
Common Denominator 2002-08-26
From Slobodanka:
What is a Common Denominator?
Answered by Penny Nom.
Adding and subtracting rational expressions 2001-05-03
From Donna:
Adding and subtracting Rational expressions. I am in grade 10 and I am a student here is an example of the questions:

1/(x+1) - 1/(x-1) = ?

Answered by Penny Nom.
Adding Fractions 1998-10-03
From Pam Bailey:
Can you help me simplfy this?

(1/2a + 1/3b) - (1/4a - 1/5b) + (1/6a - 1/7)

Answered by Harley Weston.

Fractions 1997-10-20
From Rebecca Henry:
When we add fractions, we find a common denominator and add the numerators When we multiply fractions, we simply multiply both numerators and denominators with no regard to commonality.
  1. Why do we not have to find a common denominator when multiplying?

  2. Why do we multiply both numerators and denominators?

Answered by Chris Fisher.



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