Adding and Subtracting Fractions
2. Find the lowest common denominator, then add the fractions
3. The denominators are already the same.
4. The denominators are already the same.
Note: we usually would write 18 = 2 × 9 but since we are
going to cancel everything in the numerator , it helps to write
as 18 = 1 × 2 × 9 so we can see that there will still be a 1 left in the numerator.
6. First, convert the mixed numbers to improper fractions since we know how to add improper fractions.
Now get a lowest common denominator .
Now get a lowest common denominator.
Now we can add.