Day 3 Presentation

Use the arrows to navigate through the slides.

Math Foundations: Unit 1

Day 3: Fact Families

Today's Objectives

Warm-Up: Make a Connection

If you know that...

4 x 5 = 20

...what division problem do you also know the answer to?

The Big Idea: Inverse Operations

"Inverse" is a fancy word for opposite.

Inverse operations are operations that "undo" each other. They are partners.

Addition (+)

is the inverse of

Subtraction (-)

Multiplication (x)

is the inverse of

Division (÷)

What is a Fact Family?

A fact family is a group of four math facts that all use the same three numbers. It shows the inverse relationship between multiplication and division.

12 3 4

The Fact Family for 3, 4, 12

Multiplication:

3 x 4 = 12

Multiplication:

4 x 3 = 12

Division:

12 ÷ 3 = 4

Division:

12 ÷ 4 = 3

Notice how division always starts with the biggest number!

Let's Practice Together

What is the fact family for the numbers 6, 7, and 42?

1. 6 x 7 = 42

2. 7 x 6 = 42

3. 42 ÷ 6 = 7

4. 42 ÷ 7 = 6

Independent Practice

RED

Which number is missing from this family? 2, 8, __

2 x 8 = ?

YELLOW

Write one multiplication and one division fact for:

5, 7, 35

GREEN

Write the full fact family for:

6, 8, 48

Exit Ticket

You are given one fact from a family:

9 x 4 = 36

On a piece of paper, write the other three facts in this family.

1 / 9

Day 3 Notes: Fact Families

The Big Idea: Inverse Operations

"Inverse" is a fancy word for opposite. Inverse operations are operations that "undo" each other.

Multiplication's inverse is .

Addition's inverse is .

What is a Fact Family?

A fact family is a group of four math facts that all use the same three numbers.

Example Family for 3, 4, 12:

1. 3 x 4 = 12

2. 4 x 3 = 12

3. 12 ÷ 3 = 4

4. 12 ÷ 4 = 3

Exit Ticket

You are given one fact from a family: 9 x 4 = 36. Write the other three facts in this family.

1.

2.

3.