Multiplying and Dividing Rational Fractions

When DIVIDING FRACTIONS ...

• Add the fractions.

• Get a common denominator.

• Keep the 1st fraction, Change to multiplication, and Flip the 2nd fraction to its reciprocal.

• Subtract the fractions.

When MULTIPLYING FRACTIONS...

• You MUST get a common denominator.

• Multiply across the top, multiply across the bottom.

• Add the fractions.

• Subtract the fractions.

• 1/5
• 12/72
• 7/17
• 1/6

When multiplying fractions you do what?

• KCF

• Find the least common denominator

• Multiply all of the numbers together

• Multiply top times top and bottom times bottom

Q1. What is the value of the following expression?

• -6/12

• -5/12

• 5/12

• -5/7

Find the product.  Then, simplify.

• 2/24

• 3/24

• 1/12

• 3/16

Divide (it might be helpful to re-write this problem in the usual way you see dividing fractions) as 3/8 ÷ -1/7

• -21/8 or -2 ⅝

• -3/56

• 2 ⅝

• 3/56

Divide.

• -2/3

• 2/3

• -3/8

• 3/8

Make sure your final answer is in simplest form.

Multiply. Write your answer in simplest form.

• 27/40

• -27/40

• 5/6

• -5/6