We have to look at two cases:
1st) equal denominators
To add fractions with equal denominators, just add the numerators and keep the denominator.
- To subtract fractions with equal denominators, just subtract the numerators and keep the denominator.
Take a look at the examples:
2) different denominators
To add fractions with different denominators, one solution is to obtain equivalent fractions, with denominators equal to the mmc of the denominators of fractions. Example: Sum the Fractions .
Obtaining the mmc of the denominators we have mmc (5,2) = 10.
|(10:5).4 = 8||(10:2).5 = 25|
In short: we use mmc to get the equivalent fractions and then we usually add the fractions, which will already have the same denominator, that is, we use case 1.Next: Multiplication and Division of Fractional Numbers