SOLUTION: When adding and subtracting rational numbers (fractions), why does one need a common denominator? For what reason is it recommended that one use the lowest common denominator (lcd

Question 316986: When adding and subtracting rational numbers (fractions), why does one need a common denominator? For what reason is it recommended that one use the lowest common denominator (lcd)?

Answer by checkley77(12844) (Show Source): You can put this solution on YOUR website!
1/3+1/6+2/12
The LCD is 12.
(4+2+2*1)/12=(6+2)/12=8/12=2/3 ans.
Now use 36 which is also a common denominator.
(12+6+2*3)/36=(18+6)/36=24/36=12/18=6/9=2/3 this larger common denominator requires you to work with larger numbers and requires more fraction reductions.

RELATED QUESTIONS
when you simplify a rational expression, why are the numerator and the denominator... (answered by richard1234)

When adding or subtracting fractions, how do you find equivalent fractions once the Least (answered by richard1234)

I would be grateful for any help her. I am confused and not sure how to explain. Thank... (answered by MathLover1)

How is doing operations (adding,subtracting,multiplying,and dividing) with rational... (answered by richard1234)

why don't we need a common denominator when multiplying fractions or dividing... (answered by Alan3354,ikleyn)

In adding or subtracting fractions ANY common denominator will allow you to add /subtract (answered by Alan3354)

adding and subtracting fractions to find the least common... (answered by Alan3354)

When solving a rational equation, why it is OK to remove the denominator by multiplying... (answered by rapaljer)