7.3A & 7.3B Reteach Lesson.

Unit 1 - 7.3A & 7.3B Reteach Lesson

Adding  Fractions

 $\frac{3}{4}+\frac{1}{8}\ =\ \frac{3x2}{4x2}\ +\ \frac{1}{8}\ =\ \frac{6}{8}\ +\frac{1}{8}=\ \frac{7}{8}$  

• Step 1: Find a common denominator. You can change 3/4 by multiply the numerator (top) and denominator (bottom) by 2. 

•  This converts 3/4 to 6/8.

  
  

• Step 2: Add 6/8 to 1/8 by adding the numerator (top) and keep 8 as the denominator (bottom).

• The answer is 7/8

Subtracting  Fractions

 $\frac{3}{4}\ -\frac{1}{8}\ =\ \frac{3x2}{4x2}\ -\ \frac{1}{8}\ =\ \frac{6}{8}\ -\frac{1}{8}=\ \frac{5}{8}$  

• Step 1: Find a common denominator. You can change 3/4 by multiply the numerator (top) and denominator (bottom) by 2. 

•  This converts 3/4 to 6/8.

  
  

• Step 2: Subtract 6/8 and 1/8 by subtracting the numerator (top) and keep 8 as the denominator (bottom).

• The answer is 5/8

Multiplying Fractions

 $\frac{2}{3}\ x\frac{1}{8}=\frac{2x1}{3x8}=\frac{2}{24}:Simply\ \ \frac{2\div2}{24\div2}=\frac{1}{12}$  

• Step 1: Multiply numerator (top) x numerator (top) 2x1 and denominator (bottom) x denominator (bottom) 3x8

•  Answer: $\frac{2x1}{3x8\ }=\frac{2}{24}$  

  
  

• Simplify your answer:  $\frac{2\div2}{24\div2}\ =\frac{1}{12}$  

Dividing Fractions and Mixed Numbers
 $-2\frac{1}{3}\div\frac{1}{2}=-\frac{7}{3}\div\frac{1}{2}=-\frac{7}{3}\times\frac{2}{1}=-\frac{14}{3}=-4\frac{2}{3}$  

• Step 1: Convert the mixed number to a improper fraction; $-2\ \frac{1}{3}=\ -\frac{\left(3x2\right)+1}{3}\ =\ -\frac{7}{3}$  

• Step 2: KCF  $-\frac{7}{3}\div\frac{1}{2}=\ -\frac{7}{3}\times\frac{2}{1}$  

  
  

• Step 3: Multiply numerator x numerator and denominator x denominator $-\frac{7}{3}\times\frac{2}{1}=-\frac{14}{3}\ \text{ }$ (neg x pos = neg)

• Step 4: Convert to a mixed number and simplify  $-14\ \div\ 3\ =\ -4\ \frac{2}{3}$  

Word Problem 

• There are 30 students in Coach Turners P.E. class.
  

•  $\frac{1}{3}$  of them choose to play basketball:    $\frac{1}{3}of\ 30\ =\ \frac{1}{3}\times30\ =\ \frac{1\times30}{3}\ =\ \frac{30}{3}=10$                           

•  $\frac{2}{5}$  of them choose to play football:   $\frac{2}{5}\ of\ 30=\frac{2}{5}\times30\ =\frac{2\times30}{5}=\frac{60}{5}=12$ 

• The rest of the students ran around the track.                                track students  = total students - (basketball & football students)  $30\ -\ \left(10\ +12\right)\ =\ 30\ -22\ =\ 8$                                          

Word Problem 

• There are 20 players on the Spring City basketball team. The team purchased new uniforms. The players equally split the cost for the new uniforms. The uniforms cost $450.

• How much did each team member have to pay?  $450\div20=22.50$   

• Eight basketball players have not paid for the new uniforms.        How much money still has to be collected for the uniforms?   $22.50\times8\ =180$  

Word Problem -

• Bill and Mary when to the movie theater. They purchased 2 soda, one popcorn and one candy. The tax was $1.14. If they had a $20 bill, how much money will they receive back?                    Popcorn_________$6.55                                  Candy__________$1.59                                  Soda___________$3.25

• Step 1: Add up all of the purchased items plus the tax.                    3.25 + 3.25 + 6.55 + 1.59 + 1.14 = 15.78   
  

• Step 2: Subtract the total cost from the twenty dollars.                20.00 - 15.78 = 4.22