I CAN REGROUP TO SUBTRACT MIXED NUMBERS 5.4 Regrouping to Subtract Mixed Numbers
Review from Yesterday Add or subtract __ __ 2 9
Jimmy and his mother planted a tree when it was 1 ft tall. Now the tree is 2 ft tall. How much has the tree grown since it was planted? 3 4 __ The difference in the heights can be represented by 2 – __ You will need to regroup 2 because the fraction in 1 is greater than. 1 4 __ Divide one whole of 2 into fourths.
2 1 4 __ –1 1 4 __ – 1 ______ = 2 4 __ Regroup 2 as __ 5 4 The tree has grown ft since it was planted. 1 2 __
–3 2 3 __ –3 2 3 __ ______ ______ 2 Subtract the fractions and then the whole numbers. Write 6 as a mixed number with a denominator of 3. Rename 6 as __ – 3 Additional Example 1A: Regrouping Mixed Numbers Subtract. Write each answer in simplest form.
Check It Out: Example 1A Subtract. Write each answer in simplest form. 1 6 __ Rename 7 as = –2 5 6 __ –2 5 6 __ ______ __ Subtract the fractions and then the whole numbers. 1 6 __ Write the answer in simplest form. = __ 7 – 2
2 5 __ 7 10 __ __ __ Rename 8 as = – __ – __ ______ ______ __ Subtract the fractions and then the whole numbers __ 4 10 __ 10 __ 4 10 __ 10 is a multiple of 5, so 10 is a common denominator. 8 – 6 8 – 7 = 1 Estimate the difference. 1 is close to the estimate of 1. The answer is reasonable __ Check It Out: Example 1B Subtract. Write each answer in simplest form.
Additional Example 2A: Measurement Application Li is making a quilt. She needs 15 yards of fabric. Li has 2 yards of fabric. How many more yards does she need? 3 4 __ __ Write 15 as a mixed number with a denominator of 4. Rename 15 as –2 3 4 __ –2 3 4 __ ______ ______ 12 Subtract the fractions and then the whole numbers. 4 4 __ 1 4 Li needs another 12 yards of fabric. 1 4 __
Check It Out: Example 2A Peggy is making curtains. She needs 13 yards of fabric. Peggy has 4 yards of fabric. How many more yards does she need? 5 6 __ __ Write 13 as a mixed number with a denominator of 6. Rename 13 as –4 5 6 __ –4 5 6 __ ______ ______ 8 Subtract the fractions and then the whole numbers. 6 6 __ 1 6 Peggy needs another 8 yards of fabric. 1 6 __
1. Subtract and identify the answer in simplest form. A. C. B. D. Lesson Quiz for Student Response Systems
2. Subtract and identify the answer in simplest form. A. C. B. D. Lesson Quiz for Student Response Systems
3. Subtract and identify the answer in simplest form. A. C. B. D. Lesson Quiz for Student Response Systems
4. A Dachshund weighs pounds. A Dandi Dinmont Terrier weighs 18 pounds. What is the difference, in pounds, in their weights? A. C. B. D. Lesson Quiz for Student Response Systems