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Adding Mixed Numbers. 8.2. What would you do?. 3 1/8 + 5 3/8. Procedure. Add the whole-number parts Add the fraction parts Rename into simplest form. Practice Renaming. 4 7/5 8 4/3 2 7/4. Practice. MJ page 254 Complete independently.
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What would you do? 3 1/8 + 5 3/8
Procedure • Add the whole-number parts • Add the fraction parts • Rename into simplest form
Practice Renaming 4 7/5 8 4/3 2 7/4
Practice • MJ page 254 • Complete independently. • Stand behind your chair when you are finished.
Procedure for adding unlike denominators • Add the whole-number parts • Find a common denominator • Add the fraction parts • Rename into simplest form
Spiral Practice 6 7/8 2 ½ + 4 3/8= 5 2/3 + 1 5/6= 3 4/5 + 2 ¼= 6 5/6 + 3 3/5= 1 7/8 + 8 1/6= 7 1/2 6 1/20 10 13/30 10 1/24
Pattern • Look at the following problems and determine a pattern: 1 + 1 = 3 1 2 6 1 + 1 = 5 2 3 6 1 + 1 = 7 3 4 12 1 + 1 = 9 4 5 20
Solution • When you are adding two unit fractions (numerators are 1), the sum will always be the sum of the denominators product of the denominators (How cool is that!?!)
Pattern Take a look again to see the pattern: the sum of the denominators product of the denominators 1 + 1 = 3 1 2 6 1 + 1 = 5 2 3 6 1 + 1 = 7 3 4 12 1 + 1 = 9 4 5 20
Practice the Pattern • Use the pattern on these fractions – remember this only works with unit fractions 1/3 + 1/5 = 1/12 + 1/ 4 = 1/9 + 1/7 = 1/5 + 1/15 =
Subtracting Mixed Numbers(notes) • Subtract the fractions first in case you need to borrow from the whole number. • Be sure you have common denominators before subtracting • Subtract the whole numbers. Ta Da you are a genius!
Let’s Practice Borrowing • 7 ¼ - 5 3/5= • 6 1/2 - 3 2/3= • 9 1/3 - 5 2/4= • 10 1/5 - 3 ½= 1 13/20 2 5/6 3 5/6 6 7/10
What about these? • 6 - ¼ = • 8 – 3 2/3= • 4 3/5- 1 4/5= • 5 1/6 – 2 5/6= 5 3/4 4 1/3 2 4/5 2 1/2
Mixed Number Spin • Make a spinner from a paper clip and a pencil point • Use the mixed numbers from your spin to create true number sentences • The first person to create 10 true sentences is the winner