6th Grade Math Review #2

6th Grade Math Review #2

ADDING/SUBTRACTING WITH UNLIKE DENOMINATOR

METHOD 1

LEAST COMMON DENOMINATOR

To find the least common denominator, you have to find the smallest number that both the numerator and the denominator will go into evenly. 

For example:
2 and 3 both go into 6
4 and 5 both go into 20
6 and 9 both go into 18

METHOD 2

MULTIPLY DENOMINATORS AND NUMERATORS BEFORE ADDING

Multiple Choice

Sometimes when you add fractions, you get an improper fraction as your answer. When that happens, you should:

• make the improper fraction a mixed number

• do nothing to the improper fraction

• eat some ice cream

Multiple Choice

 $4\ \frac{2}{5}\ +\ 3\ \frac{1}{10}$  If you are supposed to add these fractions, what steps would you have to do?

• 1. Find the common denominators 
  2. Make like fractions
  3. Add the fractions
  4. Add the whole numbers
  5. Simplify if possible

• 
  1. Add the fractions
  4. Ignore the the whole numbers
  5. Simplify if possible

• 1. Find the common denominators 
  2. Make like fractions
  3. Add the fractions to the whole numbers
  4. Simplify if possible
  
  
  

Borrowing from a mixed number

If the fraction of the second number is smaller than the fraction in the first number, you have to borrow from the whole number.

For example

Now I can subtract 3/3 - 2/3

REMEMBER TO SIMPLIFY

ALWAYS

Multiple Choice

• 1/12
• 1
• 2/35
• 23/25

Multiple Choice

what is the difference between

 $5\ \frac{1}{3}\ -\ 2\ \frac{2}{3\ }$  ?

•  $2\ \frac{2}{3}$  

•  $3\ \frac{1}{3}$  

Multiple Choice

6 - 2 $\frac{2}{5}$  

• 4  3/5

• 8  2/5

• 3   3/5

• 3  2/5

Multiplying Fractions

Multiplying Fractions

• 1. Convert Mixed Numbers to improper fractions

• 2. Divide down if possible

• 3. Multiply across

• 4. Convert improper fractions to mixed numbers

• 5. Simplify if possible

REMEMBER TO SIMPLIFY

ALWAYS

Multiple Select

Find the product of $\frac{16}{3}\cdot\frac{2}{7}$  in simplified form.

•  $1\ \frac{11}{21}$  

•  $\frac{18}{10}$  

•  $\frac{6}{112}$  

•  $\frac{32}{21}$  

Multiple Choice

Find the product of 

 $\frac{7}{9}\cdot\frac{1}{2}$  in simplified form

•  $\frac{9}{14}$  

•  $\frac{7}{18}$  

•  $\frac{8}{11}$  

•  $\frac{7}{11}$  

Dividing Fractions

What do you know?

Dividing Fractions

1. Invert the fraction you are dividing by (use the reciprocal).

2. Multiply across

3. Simplify (convert to a mixed number if needed).

Multiple Choice

What does reciprocal mean?

• Stay the same

• Flip

Multiple Choice

What is the reciprocal of:

 $\frac{2}{5}$  

•  $\frac{2}{5}$  

•  $\frac{5}{2}$  

Multiple Choice

What would this division sentence look like if you were solving it?

 $\frac{2}{3}\div\frac{4}{5}$  

•  $\frac{2}{3}\times\frac{4}{5}$  

•  $\frac{3}{2}\times\frac{4}{5}$  

•  $\frac{2}{3}\times\frac{5}{4}$  

Multiple Choice

What would this division sentence look like if you were solving it?

 $4\div\frac{2}{5}$  

•  $\frac{4}{1}\times\frac{2}{5}$  

•  $\frac{4}{1}\times\frac{5}{2}$  

•  $\frac{1}{4}\times\frac{2}{5}$  

Multiple Choice

Solve:

 $\frac{1}{2}\div\frac{3}{4}$  

•  $\frac{3}{8}$  

•  $\frac{4}{6}=\frac{2}{3}$  

•  $\frac{6}{4}=\frac{3}{2}=1\ \frac{1}{2}$  

Important Formulas to Know

• Area of a Rectangle = length x width

• Area of a triangle = 1/2 base x height

• Volume = bxwxh or Bh

To Find Surface Area --> Find the surface of each 2D shape and add them together!

Multiple Choice

Which label would NOT be appropriate for volume.

• square miles

• inches³

• cm³

• cubic feet

Multiple Choice

What is the area of the rectangle?

• 15 cm2

• 8 cm2

• 2 cm2

• 16 cm

Multiple Choice

Find the area of the triangle.

• 96 in²

• 48 in²

• 20 in²

Multiple Choice

Find the surface area of this figure.

• 148 cm²
• 120 cm²
• 50 cm²
• 54 cm²

Multiple Choice

• 55 yd³
• 121 yd³
• 22 yd³
• 330 yd³

Poll

How ready are you for iLearn Math Tomorrow?