+ / - Fraction Strips / LCM

Mika is calculating the Lowest Common Multiple of 4, 12, and18. She wrote the multiples of these numbers to find it.

6, 12, 18, 24, 30, 36, 42, 48, 54, 60, 66, 72...

12, 24, 36, 48, 60, 72, 84, 96, 108, 120...

18, 36, 54, 72, 90, 108, 126, 144...

The LCM is:

• 24

• 36

• 48

• 72

This work below reminds you how to convert mixed number into improper fraction.
 $3\frac{4}{5}=3+\frac{4}{5}=\frac{15}{5}+\frac{4}{5}=\frac{19}{5}$  
A faster way is  $3\frac{4}{5}$  ,  $5\times3+4\ =\ 19$ ,  $\frac{19}{5}$ .

Then   $2\frac{3}{7}$    is:

•  $\frac{14}{7}$  

•  $\frac{17}{7}$  

•  $\frac{5}{7}$  

•  $\frac{15}{7}$  

A chocolate bar was eaten by Ariana and Aaron. Ariana ate  $\frac{3}{8}$ and Aaron ate  $\frac{3}{5}$  . The fraction that represents what they both ate is: 

•  $\frac{6}{13}$  

•  $\frac{6}{40}$  

•  $\frac{33}{40}$  

•  $\frac{39}{40}$  

Tags

CCSS.5.NF.A.1

CCSS.5.NF.A.2

 This picture represents a part of of fraction strips chart.
According to the image, choose all the correct statements.

•  $\frac{1}{12}+\frac{1}{12}+\frac{1}{12}+\frac{1}{12}=\frac{1}{6}+\frac{1}{6}$  

•  $\frac{1}{5}+\frac{1}{5}+\frac{1}{5}=\frac{1}{10}+\frac{1}{10}+\frac{1}{10}+\frac{1}{10}+\frac{1}{10}+\frac{1}{10}$  

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

•  $\frac{1}{12}+\frac{1}{12}+\frac{1}{12}+\frac{1}{12}+\frac{1}{12}=\frac{1}{5}+\frac{1}{5}$  

Tags

CCSS.4.NF.A.1

CCSS.5.NF.B.5B

Here you have another part of the Fraction Strips Chart.

Choose the WRONG answer according to this picture.

• $\frac{1}{3}+\frac{1}{3}>\frac{1}{2}$

• $\frac{1}{4}+\frac{1}{4}<\frac{1}{5}+\frac{1}{5}+\frac{1}{5}$

• $\frac{1}{3}+\frac{1}{3}<\frac{1}{5}+\frac{1}{5}+\frac{1}{5}$

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

Tags

CCSS.4.NF.A.2

If a mixed number  $2\frac{4}{5}$  is 

an addition  $2+\frac{4}{5}$  , 

then  $3\frac{2}{9}+\ 3\frac{2}{9}$ will be:

•  $6\frac{5}{18}$  

•  $6\ \frac{4}{9}$  

•  $3\ \frac{4}{9}$  

•  $6\frac{2}{18}$  

Tags

CCSS.4.NF.B.3A

Emilia made a cake and left it for her son, Jacob, to eat part of it. Jacob ate one-fourth and Emilia consumed two-fifths.

To solve that problem, we can write the expression:
 $1\ -\ \frac{1}{4}-\frac{2}{5}$   or that  $1-\left(\frac{1}{4}+\frac{2}{5}\right)$  
Choose all the right answers according to this expression.

• 1/4 and 2/5 needs to be subtracted from the whole.

• 1 represents the whole cake.

• Both expressions are right. They will have the same answer.

• The last expression is wrong because we cannot use addition to solve that problem.

Tags

CCSS.5.NF.A.1

CCSS.5.NF.A.2

 Think of this expression:
 $\frac{17}{5}=\frac{15}{5}+\frac{2}{5}=\frac{5}{5}+\frac{5}{5}+\frac{5}{5}+\frac{2}{5}=$ 

 $1+1+1+\frac{2}{5}=3\frac{2}{5}^{ }$  .
So, in 17/5 we have 3 wholes and 2/5.

Jonathan consumed  $\frac{12}{5}$  cookies and Lily  $\frac{10}{3}$  . It is right that they ate together:

• 5 cookies (wholes)

• 4 cookies (wholes)

• 6 cookies (wholes)

• 3 cookies (wholes)

Tags

CCSS.4.NF.B.3A

Suppose you need to solve:
 $\frac{7}{15}-\frac{5}{12}$  .
To obtain the right result: 

• We can do 15x12 and 12x15 with the denominators and 7 - 5 with numerators.

• We can simply do 7 - 5 and 15 - 12.

• We can calculate the LCM of 15 and 12 to find a common denominator before finding the equivalent fractions to subtract.

• Before subtracting, we do 15x15 and 15x7 and also 12x5 and 12x12.

Tags

CCSS.7.NS.A.1C

Solving

  $2-\frac{3}{4}+\frac{9}{5}=$  

we obtain:

•  $1\frac{6}{9}$  

•  $1\frac{7}{20}$  

•  $2\frac{3}{20}$  

•  $3\frac{1}{20}$  

Tags

CCSS.7.NS.A.1C