1. Objective: Students will be able to subtract mixed numbers involving renaming (6-6).

2. Vocabulary:  None

3. Steps:  Read all directions!!!!!!!!  Write the problem.  Find the LCD (LCD=LCM).  Find new numerators.  Rename.  Subtract.  Simplify.

4. Whole # and a fraction:  Rename by borrowing one from the whole #.  Add your numerator and denominator in top fraction only (this is your numerator).  Keep same denominator.  Subtract.  Simplify.

5. Whole # only on top:  Rename by borrowing one from the whole number.  Next, look at the denominator in the bottom fraction. This becomes both your numerator and denominator. Second fraction stays the same.  Subtract.  Simplify.

6. Examples Find 4 – 1 2/3 4 - 1 2/3 - 1 2/3

7. Examples Find 4 – 1 2/3 4 3 3/3 Rename 4 as 3 3/3. 4 3 3/3 Rename 4 as 3 3/3. - 1 2/3 - 1 2/3 - 1 2/3 - 1 2/3

8. Examples Find 4 – 1 2/3 4 3 3/3 Rename 4 as 3 3/3. 4 3 3/3 Rename 4 as 3 3/3. - 1 2/3 - 1 2/3 - 1 2/3 - 1 2/3 1/3 Subtract the fractions 1/3 Subtract the fractions

9. Examples Find 4 – 1 2/3 4 3 3/3 Rename 4 as 3 3/3. 4 3 3/3 Rename 4 as 3 3/3. - 1 2/3 - 1 2/3 - 1 2/3 - 1 2/3 2 1/3 Subtract the fractions 2 1/3 Subtract the fractions Then subtract the Then subtract the whole #s. whole #s.

10. Examples Find 17 ¼ - 3 5/8 17 ¼ 17 ¼ - 3 5/8 - 3 5/8

11. Examples Find 17 ¼ - 3 5/8 17 ¼ 17 2/8 The LCM of 4 & 8 is 8 17 ¼ 17 2/8 The LCM of 4 & 8 is 8 - 3 5/8 - 3 5/8 - 3 5/8 - 3 5/8

12. Examples Find 17 ¼ - 3 5/8 17 ¼ 17 2/8 The LCM of 4 & 8 is 8 17 ¼ 17 2/8 The LCM of 4 & 8 is 8 - 3 5/8 - 3 5/8 - 3 5/8 - 3 5/8 17 2/8 16 10/8 Since 5/8 is greater 17 2/8 16 10/8 Since 5/8 is greater - 3 5/8 - 3 5/8 than 2/8 you must - 3 5/8 - 3 5/8 than 2/8 you must rename 17 2/8 as 16 rename 17 2/8 as 16 10/8 10/8

13. Examples Find 17 ¼ - 3 5/8 17 ¼ 17 2/8 The LCM of 4 & 8 is 8 17 ¼ 17 2/8 The LCM of 4 & 8 is 8 - 3 5/8 - 3 5/8 - 3 5/8 - 3 5/8 17 2/8 16 10/8 Since 5/8 is greater 17 2/8 16 10/8 Since 5/8 is greater - 3 5/8 - 3 5/8 than 2/8 you must - 3 5/8 - 3 5/8 than 2/8 you must rename 17 2/8 as 16 rename 17 2/8 as 16 10/8 10/8 16 10/8 Subtract the fractions 16 10/8 Subtract the fractions - 3 5/8 then subtract the whole - 3 5/8 then subtract the whole 13 5/8 #s. 13 5/8 #s.

14. Examples A male California sea lion grows to be between 6 ½ and 8 feet long. Find the difference between the greatest and least lengths. 8 - 6 ½ - 6 ½

15. Examples A male California sea lion grows to be between 6 ½ and 8 feet long. Find the difference between the greatest and least lengths. 8 7 2/2 Rename 8 as 7 2/2 8 7 2/2 Rename 8 as 7 2/2 - 6 ½ - 6 ½ - 6 ½ - 6 ½

16. Examples A male California sea lion grows to be between 6 ½ and 8 feet long. Find the difference between the greatest and least lengths. 8 7 2/2 Rename 8 as 7 2/2 8 7 2/2 Rename 8 as 7 2/2 - 6 ½ - 6 ½ - 6 ½ - 6 ½ 1 ½ Subtract the fractions 1 ½ Subtract the fractions then subtract the whole then subtract the whole #s. #s.