Dividing Fractions

How many quarters are in 2?

• Using pictures, groupings, common denominators, repeated subtraction, etc. show your answer in as many ways as you can

Activity:

• In your group complete the math problems provided on the task card

• Be prepared to share your solutions

Problem 1

A group of friends buys 3 pizzas to share equally. Each friend receives 3/8 of the pizza. Show different ways to find the total number of friends in the group.

Problem 2

Amy, Sue and Alex bought ¼ Kg of trail mix to share equally. Show different ways to determine how much trail mix each person will receive.

Problem 3

Sandra’s printer can print 5 pages in 2/3 of a minute. Show different ways to determine how many pages Sandra’s printer can print in 1 minute.

Problem 4

The area of a rectangle is 2 5/8 square units. The length of the rectangle is 1 ¾ units. Show different ways to determine the width of the rectangle.

Ways to Divide Fractions

1. Partitive Division2. Quotitive Division3. Unit Rate Division4. Common Denominator Algorithm

Partitive Division

• Determining equal parts or shares of a wholeExample: share 4 cookies among 3 people

1

Quotitive Division

• How many shares can be measured out of the whole?

• Four cookies are divided into thirds, how many shares are there?

4 12 shares

Unit Rate Division

• A unit rate is the quantity associated with a single unit of another quantity

• Example: $8 per hour, 45 words per minute• If it takes of a gallon of water to fill a pail full, how many gallons will fill the pail?

3 = 4 =

Common Denominator Algorithm

• How many sets of are in ?

3

Practice

• Complete the questions on BLM 5.9.2 in your notebook

Ways to Divide Fractions

1. Partitive Division2. Quotitive Division3. Unit Rate Division4. Common Denominator Algorithm5. Invert and Multiply Rule

Invert and Multiply Rule

Consider this question:

Invert and Multiply Rule

• When dividing by a fraction always:a. Record the first number or fractionb. Change the division operator to multiplicationc. Invert the fraction you are dividing byd. Multiply the numeratorse. Multiply the denominatorsf. Simplify the answer into lowest terms

Example

Practice

• Complete the following questions in your notebook:

a. b.

c. 2 d. 3 1