3-2 Adding and Subtracting Fractions with Like Denominators Shade the model to help solve each problem. 1.) 2.) 1 8 3 8 To add or subtract fractions with like denominators: 1.) Add or subtract the numerators 2.) Keep the same denominator 3.) Reduce the fraction 4.) Rename improper fractions Demonstrate Understanding 1.) 5 2 7 7 9 2.) 3.) 3 _1 4.) 11 4 4 12 9 6 7 _7 12 3-2 Adding and Subtracting Fractions with Unlike Denominators Use the model to add the fractions. 1.) a.) What happens when you try to add fractions with different denominators? b.) What do we need to do when the denominators are different? To add or subtract fractions with unlike denominators 1.) Find the LCM of the denominators 2.) Rewrite each fraction using the LCM as the denominator 3.) Add or subtract the numerators, keeping the denominator 4.) Reduce and rename as a mixed number if necessary LCM: Listing method 9: 6: Try some: 2.) 1.) = = + = = 3.) 4.) 5.) 6.) 7.) A circus has ten seating sections. Eight sections are filled for the first show. Six sections are filled for the second show. How much more of the entire seating area is filled for the first show? 8.) A park is currently of an acre. A local property owner donated added to the park. What is the new area of the park? acre to be