## Key Concepts

- Applying the multiplication facts
- Associative(grouping) property of multiplication

**3.4. Practice multiplication facts & The associate property: multiply with 3 factors**

### What is a multiplication fact?

A multiplication fact is an answer to a multiplication calculation.

Some examples of multiplication facts.

- 4 × 3 = 12 (the multiplication fact is 12)
- 7 × 8 = 56 (the multiplication fact is 56)

### What is the associative property of multiplication?

The associative property of multiplication states that the way in which the numbers are grouped in a multiplication problem does not affect or change the product of those numbers.

**Associative Property of Multiplication**

Example for the associative property of multiplication.

(**6 ****× ****5**** **) × 7 = 6 × (**5 × 7**)

(**30**) × 7 = 6 × (**35**)

210 = 210

### 3.4.1 Applying the multiplication facts

**Example1:**

Mr Ling arranged fruit salad bowls for his friends. He placed 7 rows of bowls, and each row had 4 bowls. How many fruits does the salad bowl Ling arrange?

**Solution:**

**Find 7 x 4.**

**One way:**

**Step1**: Draw a picture to find 7 x 4.

7 x 4 means 7 groups of 4

Combine groups to find the product.

4 feet in each section.

**Step2:** Multiply 7 x 4 = 28.

**Another way:**

Use known facts to find 7 x 4.

Use 5 and 2 as a fact to help.

Add 20 + 8 = 28.

**Example2:**

Mischa bought 6 packs of balls. Each packet has 3 balls. How many balls did Mischa buy?

**Solution:**

6 x 3 means 6 groups of 3.

Combine groups to find the product.

3 feet in each section.

6 x 3 = 18.

**Another way:**

Use known facts to find 6 x 3.

Use 4 and 2 as a fact to help.

Add 12 + 6 = 18.

### 3.4.2 Associative(grouping) property of multiplication

**Example1: **

Ricardo has 6 pages of stickers in an album. Each page has 6 rows with 4 stickers in each row. How many stickers are there in Ricardo’s album?

**Solution:**

Multiply (6 x 6) x 4.

One way’s

Find 6 x 6 first.

**Another way:**

6 x (6 x 4)

Find 6 x 4 first.

**Example2:**

Sarah is joining 5 sections of grid. Each section has 3 rows with 4 squares in each row. How many squares are there in these 5 sections? Find 5 x 3 x 4.

**Solution:**

Multiply (5 x 3) x 4.

**One way’s**

Find 5 x 3 first.

15 rows 4 squares in each row.

There are 60 squares in all.

**Another way:**

5x (3 x 4)

Find 6 x 4 first.

## EXERCISE

- 1. Use known facts and strategies to find the product.

a. 8 x 2 =

b. 2 x 6=

c. 8 x 7= - 2. To find 8 x 4, how does knowing 6 x 4 = 24 help you?
- 3. What is 7 x 3?
- 4. Use the associative property of multiplication to find the missing number.

a. 7 x (2 x 4) = (7×2) x

b. 4x (3 x 2) = (4 x 3) x - Use the associative property of multiplication to find the product.

a. 2 x 3 x 5 =

b. 5 x 6 x 3= - Mary says she can find the product for 2 x 4 x 7 by solving 4 x2 x7. Is Mary correct? Explain.
- Which known facts can you use to find 9 x 5?
- Farmer has a garden with three sections of vegetables. Each section of vegetables has 5 rows with 6 plants in each row. How many plants does the farmer plant?
- A movie theatre has 2 sections. Each section has 6 rows and each row has 8 seats. Find the total number of seats are there in the movie theatre.
- Fill in the blanks for the following:

4x (3 x 2) = (4 x 3) x

6x (2 x 5) = (6 x2) x

(20 x 5) x 11 = 20 x (11x )