That's a "common" denominator. "Common" means "same for both" or "same for all".
A "common denominator"
That's a common denominator.
Common denominator
That means that two or more fractions have the SAME denominator.
First, change it so that the two fractions have the same denominator (by changing the fractions into equivalent fractions). Once the two fractions have the same denominator, it is simply a case of subtracting the numerators, leaving the denominator the same. Finally, reduce the fraction to its lowest terms (if possible).
When adding two or more unlike fractions, yes.
First, find a common denominator for the two (or more) fractions. Then, for each fraction, multiply numerator and denominator by the same number (different numbers for different fractions, though), to convert to the common denominator.
Common Denominator means that the denominators in two (or more) fractions are common, or the same. The common denominator is important because before you can add or subtract fractions, the fractions need to have a common denominator.Sometimes fractions have different denominators, like 2/3 and 3/4. If you want to add or subtract them, they need to have the same denominator. In order to do that, you find a common denominator which is the same thing as a common multiple, only with denominators.
Nothing actually happens. You are now in a position where the fractions may be added or subtracted more easily but that is all.
least common denominator
This is when two or more fractions have the same denominator (the number on the bottom). You can find a common denominator by trying different multiples of the fractions. I'm also aware that it's the name of a song by Justin Bieber on his new album! :D
Subtract as if there were no denominators.