Need To Know

Prime Factoring

Operations on
Fractions

Simplify (Reduce)

Multiply

Divide

Add

Subtract

**Vocabulary**

Definitions:

Prime numbers – are numbers that can only

be factored by one and itself.

{

Prime factoring - means to write a

number as a product of only prime numbers.

**Prime Factoring**

Prime factor 48

Prime factor 420

**Reducing Fractions**

Reduce 5/15 9/21

Reduce 279/310

**Multiplication of Fractions**

Simplify each expression

Recall fraction multiplication

**Division of Fraction**s

Recall – Division of fractions is the same

as

Simplify:

end

**1.3.B Add and Subtract Fractions**

Need To Know

How to add/subt.
fractions with same

denominator

Rename fractions

Find Least Common
Denominator

How to add/subt.
fractions with different

denominator

**Add and Subtract Fractions**

Recall the method to add fractions

Recall the method to subtract fractions

**Renaming Fractions**

Recall how to use the “fancy one” to

rename fractions.

**Least Common Denominator**

Definition –

The least common denominator (LCD) for a

set of denominators is the smallest multiple

that each denominator can divide into evenly.

Examples: Find the LCD

**How to find the LCD**

There are three ways to find LCD’s

Use intuition

Use a list of multiples

Use the prime factoring method

**How to find the LCD**

Listing multiples method

Example: Find the LCD of 12 and 18

**How to find the LCD
**

Example: Find the LCD of 60 and 42.

1. Prime factor each

denominator

2. Create a product

using each factor

raised to the

highest exponent

that occurs in any

one factoring

**Add and Subtract Fractions**

Recall how to add fraction

**How to + or – fraction
**

Find the LCD

Rename each fraction

(use the “fancy one”)

Add numerators

Reduce

**Practice**

**
How to + or – fraction**

1. Find the LCD

2. Rename (use the “fancy one”)

3. Add numerators

4. Reduce

Simplify:

Simplify:

**Practice**

**
How to + or – fraction**

1. Find the LCD

2. Rename (use the “fancy one”)

3. Add numerators

4. Reduce

Simplify:

Simplify:

end