FRACTIONS! A slight review of all 4 operations

OBJECTIVE Today we will review the basic operations, add, subtract, multiply and divide, of fractions! NOOOOoooo!! Not fractions!!! YES!!! FRACTIONS!!!!

Let’s start easy on ya ;-)

Multiply Fractions To multiply fractions, multiply the numerators and multiply the denominators.

Multiply. Write in simplest form X 1212 X x 1 2 x 3 =   Multiply the numerators Multiply the denominators = 1616

example 2 x x 2 = x  Write 2 as Multiply the numerators 2121 Multiply the denominators   2 x 3 1 x 4 = 6464 = = 3232 SIMPLIFY 

YOUR TURN x 3 x 1 5 x 2 = ) 2) 2323 x 4 2 x 4 3 x x= == 8383

Simplify Before Multiplying If the numerator and denominator of either fraction have common factors, you can simplify before multiplying. THIS WILL MAKE YOUR LIFE EASIER IN THE END!!

Multiply Mixed Numbers Find x Rewrite the mixed number as an improper fraction = X 22 5 = 1 x 22 2 x 5 = 11 5 / / 1 11 = 1 x 11 1 x 5 SIMPLIFY BEFORE MULTIPLYING TO MAKE LIFE EASIER!!

example x x 18 5 Write mixed #’s as improper fractions  11 x 18 6 x 5 = = / / = 11 x 3 1 x 5 (take out common factor) 

Dividing Fractions To divide by a fraction, multiply by its reciprocal. Two numbers whose product is 1 are reciprocals The reciprocal of is =x x= 1

8 ÷ 2 = 4 8 x = reciprocals _____   same results _____   Dividing 8 by 2 gives the same result as multiplying 8 by the reciprocal of 2, or 1212

Dividing fractions is simple as pie; flip the second number and multiply!

Divide by a Fraction Find ÷ =x ÷ Multiply by the reciprocal of, which is  = x = 3 x 2 4 x = Multiply SIMPLIFY!!!   = 6464

YOUR TURN!! _ x = 5 x 3 6 x 2 = = 5454 Multiply by the reciprocal 

Divide by Mixed Numbers ÷ ÷ 3232 Rename 1 as an improper fraction 1212  x = =x Multiply by the reciprocal  = 15 x 2 1 x 3 = 30 3 =10 Rewrite whole #’s over 1 

YOUR TURN!! x ÷ ÷ Rename the mixed #’s as improper fractions Multiply by the reciprocal   x / / 1 2  Simplify before multiplying 1 x 7 2 x = = = = =

AANNDDD NOOWWW… The semi (but not really) harder part! OH NOOOOOOO!!

ADDING AND SUBTRACTING FRACTIONS!!

Fractions that have the same denominators are called like fractions

Add and Subtract like fractions 1) add/subtract numerators 2) write the result over the denominator 3) SIMPLIFY!!!

EXAMPLE = = = = 4545 =

YOUR TURN!! =-= 2323 = = == 1) 2)

Add and Subtract unlike fractions 1) Find the LCD 2) Rewrite your fractions using the LCD. (you will now have like fractions) 3) Add/subtract the like fractions 4) SIMPLIFY

1212 1) = 1 x 2 6 = 2 x 3 LCD= 2 x 3 = ) ?6?6 = =  Find the LCD  Rewrite using the LCD = ) = )  SIMPLIFY  Add/Subtract = EVALUATE

YOUR TURN!! = LCD = = = = = 41 24