Compose and Decompose Fractions

Write the fraction as a sum of unit fractions.

 $\frac{4}{8}$  

•  $\frac{2}{8}+\frac{2}{8}=\frac{4}{8}$  

•  $\frac{3}{8}+\frac{1}{8}=\frac{4}{8}$  

•  $\frac{1}{8}+\frac{1}{8}+\frac{1}{8}+\frac{1}{8}$  

•  $\frac{1}{8}+\frac{1}{8}+\frac{1}{8}+\frac{1}{8}=\frac{4}{8}$  

Tags

CCSS.3.NF.A.1

Write the fraction as a sum of unit fractions.

 $\frac{6}{6}$  

•  $\frac{1}{1}+\frac{1}{1}+\frac{1}{1}+\frac{1}{1}+\frac{1}{1}+\frac{1}{1}=\frac{6}{6}$  

•  $\frac{1}{6}+\frac{1}{6}+\frac{1}{6}+\frac{1}{6}+\frac{1}{6}+\frac{1}{6}=\frac{6}{6}$  

•  $\frac{3}{6}+\frac{3}{6}=\frac{6}{6}$  

•  $\frac{6}{6}=\frac{6}{6}$  

Tags

CCSS.4.NF.B.3

What does decompose mean?

• to put together

• to combine

• to add

• to break apart

Tags

CCSS.3.OA.D.9

Mrs. Burdick took the fraction  $\frac{3}{3}$  and decomposed it into a sum of unit fractions. 

She decomposed it like this  $\frac{3}{3}=\frac{1}{1}+\frac{1}{1}+\frac{1}{1}$  

Do you think Mrs. Burdick is correct or incorrect in her work? Why?

• Mrs. Burdick is correct because  $\frac{1}{1}+\frac{1}{1}+\frac{1}{1}=\frac{3}{3}$   .  $1+1+1=3$  for the numerator and denominator.

• Mrs. Burdick is correct because she did it right. 

• Mrs. Burdick is incorrect because she added it wrong.

• Mrs. Burdick is incorrect because the denominator did not stay the same. Also,  $\frac{1}{1}$  is not a unit fraction. It is a whole.  $\frac{1}{1}+\frac{1}{1}+\frac{1}{1}=\frac{3}{1}$  

Tags

CCSS.3.NF.A.1

CCSS.3.NF.A.3

What does $\frac{1}{5}+\frac{1}{5}+\frac{1}{5}+\frac{1}{5}$  equal?

•  $\frac{5}{5}$  

•  $\frac{4}{20}$  

•  $\frac{5}{20}$  

•  $\frac{4}{5}$  

Tags

CCSS.3.NF.A.1

CCSS.3.NF.A.3

Using the model, create an equation that uses unit fractions for the fraction strip.

• $\frac{1}{4}+\frac{1}{4}+\frac{1}{4}+\frac{1}{4}=\frac{4}{4}$

• $\frac{1}{6}+\frac{1}{6}+\frac{1}{6}+\frac{1}{6}=\frac{4}{6}$

• $\frac{2}{6}+\frac{2}{6}=\frac{4}{6}$

• $\frac{1}{6}+\frac{1}{6}+\frac{1}{6}+\frac{1}{6}+\frac{1}{6}+\frac{1}{6}=\frac{6}{6}$

Tags

CCSS.3.G.A.2

CCSS.3.NF.A.1

CCSS.3.NF.A.3

Decompose the following fraction:
6/10

• 1/6 + 5/6
• 2/10 + 4/10
• 3/10 + 2/10
• 1/10 + 1/10 + 3/10

Tags

CCSS.3.NF.A.1

CCSS.3.NF.A.3

How can you get 3/4?

• 1/4 + 1/4
• 2/4 + 1/4
• 1/4 + 1/4 + 1/4 + 1/4
• 3/4 + 1/4

Tags

CCSS.3.NF.A.1

CCSS.3.NF.A.3

Decompose 5/12 into the sum of its unit fractions.

• 1/5+1/5+1/5+1/5+1/5 = 5/12
• 1/12+1/12+1/12+1/12+1/12 = 5/12
• 1/5+1/12+1/5+1/12+1/5 = 5/12
• 4/12+1/12 = 5/12

Tags

CCSS.3.NF.A.1

CCSS.3.NF.A.3

Kyleigh made a giant cookie to eat for lunch. She ate 1/5 of it and felt sick.  She gave the rest of the giant cookie to Noelle.  How much of the cookie did Noelle have? 

• 4/5
• 1/5
• 3/5
• 5/5

Tags

CCSS.3.NF.A.1

CCSS.3.NF.A.2

CCSS.3.NF.A.3