In adding and subtracting fractions with unlike denominators, you have to get a least common denominator which is exactly like the least common multiple it just so happens to be in the denominator.

There are two rules to remember when adding or subtracting fractions. The fractions need to have a common denominator. This means the denominator has to be the same. You only need to add or subtract ...

Unit fractions can be compared by looking at the denominator, or the number of equal pieces the whole has been divided into. The denominator is the number below the division bar. Unit fractions always ...