Key Concepts

• Add mixed numbers with a common denominator: Method 1.
  1. Add the whole numbers.
  2. Add the fractions.
  3. Simplify, if possible.
• Add mixed numbers with a common denominator: Method 2.
  1. Convert the mixed numbers to improper fractions.
  2. Add the improper fractions.
  3. Rewrite as a mixed number.
  4. Simplify, if possible.
• Subtract mixed numbers with common denominators: Method 1.
  1. Rewrite the problem in vertical form.
  2. Compare the two fractions.  If the top fraction is larger than the bottom fraction, go to Step 3. If not, in the top mixed number, take one whole and add it to the fraction part, making a mixed number with an improper fraction.
  3. Subtract the fractions.
  4. Subtract the whole numbers.
  5. Simplify, if possible.
• Subtract mixed numbers with common denominators: Method 2.
  1. Rewrite the mixed numbers as improper fractions.
  2. Subtract the numerators.
  3. Rewrite the answer as a mixed number.
  4. Simplify the fraction part, if possible.
• Add and Subtract mixed numbers with different denominators.
  1. Convert the fractions to equivalent fractions with the LCD.
  2. Follow the steps for adding or subtracting fractions with like denominators.