1. 5-8 Adding and Subtracting Mixed Numbers Course 1 Warm Up Warm Up Lesson Presentation Lesson Presentation Problem of the Day Problem of the Day

2. Course 1 5-8 Adding and Subtracting Mixed Numbers Warm Up Add. Write each answer in simplest form. 1. –2. + 3. + 4. – 7 12 __ 1 2 3 11 __ 2 3 1 6 3 4 11 12 __ 1 3 1 12 __ 31 33 __ 11 12 __ 7 12 __

3. Course 1 5-8 Adding and Subtracting Mixed Numbers Problem of the Day The sum of every row, column and diagonal is the same. Complete the magic square. 1 3 4 __ 11 12 ___ 1 1 3 __ 1 1 6 12 1 1 __ 5 6 2 3 1 4 1

4. Learning Goal Assignment Learn to add and subtract mixed numbers with unlike denominators. Course 1 5-8 Adding and Subtracting Mixed Numbers

5. Course 1 5-8 Adding and Subtracting Mixed Numbers Additional Example 1A: Adding and Subtracting Mixed Numbers Find the sum. Write the answer in simplest form. 1 8 __ 5 6 3 1 8 3 6 48 __ Multiply the denominators. 8 · 6 = 48 +1 5 6 __ + 1 40 48 __ ______ Write equivalent fractions with a denominator of 48. 4 = 4 46 48 __ 23 24 __ Add the fractions and then whole numbers, and simplify. A. 3 + 1

6. Course 1 5-8 Adding and Subtracting Mixed Numbers Try This: Example 1A Find the sum. Write the answer in simplest form. 1 4 __ 1 6 2 1 4 2 6 24 __ Multiply the denominators. 4 · 6 = 24 +3 1 6 __ + 3 4 24 __ ______ Write equivalent fractions with a denominator of 24. 5 = 5 10 24 __ 5 12 __ Add the fractions and then whole numbers, and simplify. A. 2 + 3

7. Course 1 5-8 Adding and Subtracting Mixed Numbers Additional Example 1B: Adding and Subtracting Mixed Numbers Find the difference. Write the answer in simplest form. 2 3 __ 1 4 5 2 3 5 8 12 __ The LCD of the denominators is 12. –1 1 4 __ – 1 3 12 __ ______ Write equivalent fractions with a denominator of 12. 4 5 12 __ Subtract the fractions and then the whole numbers. B. 5 – 1

8. Course 1 5-8 Adding and Subtracting Mixed Numbers Try This: Example 1B Find the difference. Write the answer in simplest form. 1 2 __ 3 7 4 1 2 4 7 14 __ The LCD of the denominators is 14. –1 3 7 __ – 1 6 14 __ ______ Write equivalent fractions with a denominator of 14. 3 1 14 __ Subtract the fractions and then the whole numbers. B. 4 – 1

9. Course 1 5-8 Adding and Subtracting Mixed Numbers Additional Example 1C: Adding and Subtracting Mixed Numbers Find the sum. Write the answer in simplest form. 1 2 __ 4 5 2 1 2 2 5 10 __ The LCD of the denominators is 10. +4 4 5 __ + 4 8 10 __ ______ Write equivalent fractions with a denominator of 10. 6 = 7 13 10 __ 3 10 __ Add the fractions and then the whole numbers. 6 = 6 + 1 13 10 __ 3 10 __ C. 2 + 4

10. Course 1 5-8 Adding and Subtracting Mixed Numbers Try This: Example 1C Find the sum. Write the answer in simplest form. 7 8 __ 2 3 2 7 8 2 21 24 __ The LCD of the denominators is 24. +4 2 3 __ + 4 16 24 __ ______ Write equivalent fractions with a denominator of 24. 6 = 7 37 24 __ 13 24 __ Add the fractions and then the whole numbers. 6 = 6 + 1 37 24 __ 13 24 __ C. 2 + 4

11. Course 1 5-8 Adding and Subtracting Mixed Numbers Additional Example 1D: Adding and Subtracting Mixed Numbers Find the difference. Write the answer in simplest form. 2 3 __ 2 9 6 2 3 6 6 9 Think: 9 is a multiple of 3, so 9 is the LCD. –3 2 9 __ – 3 2 9 __ ______ Write equivalent fractions with a denominator of 9. 3 4 9 __ Subtract the fractions and then the whole numbers. D. 6 – 3

12. Course 1 5-8 Adding and Subtracting Mixed Numbers Try This: Example 1D Find the difference. Write the answer in simplest form. 3 4 __ 1 8 7 3 4 7 6 8 Think: 8 is a multiple of 4, so 8 is the LCD. –2 1 8 __ – 2 1 8 __ ______ Write equivalent fractions with a denominator of 8. 5 5 8 __ Subtract the fractions and then the whole numbers. D. 7 – 2

13. Course 1 5-8 Adding and Subtracting Mixed Numbers Additional Example 2: Measurement Application The length of Jen’s kitten’s body is 10 inches. Its tail is 5 inches long. What is the total length of its body and tail? 1 4 __ 1 8 1 4 1 8 10 1 4 __ 10 2 8 __ Find a common denominator. Write equivalent fractions with the LCD, 8, as the denominator. +5 1 8 __ + 5 1 8 __ ______ Add the fractions and then the whole numbers. 15 3 8 __ The total length of the kitten’s body and tail is 15 inches. You can use mental math to find an LCD. Think: 8 is a multiple of 4 and 8. Helpful Hint 3 8 __ Add 10 + 5

14. Course 1 5-8 Adding and Subtracting Mixed Numbers Try This: Example 2 The length of Regina’s mouse’s body is 2 inches. Its tail is 2 inches long. What is the total length of its body and tail? 2 3 __ 1 6 2 3 1 6 2 2 3 2 4 6 Find a common denominator. Write equivalent fractions with the LCD, 6, as the denominator. +2 1 6 __ + 2 1 6 __ ______ Add the fractions and then the whole numbers. 4 5 6 __ The total length of the mouse’s body and tail is 4 inches. 5 6 __ Add 2 +2

15. Lesson Quiz Find each sum or difference. Write the answer in simplest form. 1. 7 – 42. 9 + 7 3. 6 + 1 4. 10 – 4 5. Miles worked 5 hours on Friday and 8 hours on Saturday. How many total hours did he work? 11 12 __ 2 3 1 6 3 8 7 8 3 10 __ 2 5 1 6 2 3 3 4 3 1 4 16 13 24 __ 8 7 40 __ 6 7 30 __ 14 hours 5 12 __ Course 1 5-8 Adding and Subtracting Mixed Numbers