LEARN · PRACTISE · DISCOVER
What Is Multiplication? Equal Groups
Imagine you have 4 bags with 3 apples in each bag. How many apples do you have? You could count every apple, or add 3 + 3 + 3 + 3. But there is a faster way: multiplication. Multiplication is a quick way to add equal groups. In this lesson you will learn what multiplication means and how to write it.
Equal groups
Groups are equal when each group has the same number of things.
| Situation | Equal groups? |
|---|---|
| 3 plates with 4 cookies each | Yes |
| 2 boxes with 6 pencils each | Yes |
| 1 bag with 2 marbles and 1 bag with 5 marbles | No |
We can only multiply when the groups are equal.
Describing equal groups
We describe equal groups like this: “4 groups of 3“. The first number tells how many groups. The second number tells how many are in each group.
Writing multiplication
“4 groups of 3” is written as a multiplication sentence:
4 × 3 = 12
- The symbol × means “times” or “groups of”.
- 4 and 3 are called factors.
- 12, the answer, is called the product.
Repeated addition
Multiplication is the same as adding the same number again and again:
| Repeated addition | Multiplication | Product |
|---|---|---|
| 3 + 3 + 3 + 3 | 4 × 3 | 12 |
| 5 + 5 | 2 × 5 | 10 |
| 2 + 2 + 2 + 2 + 2 + 2 | 6 × 2 | 12 |
When there are many groups, multiplication is much faster than writing out all the additions.
Multiplication in real life
We use multiplication all the time, even if we do not notice it:
- There are 7 days in a week. How many days are in 3 weeks? 3 × 7 = 21.
- A spider has 8 legs. How many legs do 2 spiders have? 2 × 8 = 16.
- Eggs often come in boxes of 6. How many eggs are in 4 boxes? 4 × 6 = 24.
Example
Ms Lee is setting up for art class. She puts 5 tables in the room and places 4 paintbrushes on each table. How many paintbrushes does she need?
There are 5 equal groups of 4. We write 5 × 4. Adding, 4 + 4 + 4 + 4 + 4 = 20. So 5 × 4 = 20 paintbrushes.
Tip: When you see the words “each”, “every” or “per” in a problem, think about equal groups. Multiplication might be the tool you need.
Drawing equal groups
You can always draw a picture to help. Draw a circle for each group, then put the same number of dots in each circle. Count the dots to find the product. Pictures are a great way to check your thinking.
Key takeaways
- Multiplication is a fast way to add equal groups.
- “4 groups of 3” is written 4 × 3.
- The numbers we multiply are factors; the answer is the product.
- Words like “each” and “every” often signal multiplication.
Practice
Write a multiplication sentence and find the product:
- 3 groups of 5
- 6 + 6 + 6 + 6
- 2 cars with 4 wheels each
Answers: 1 is 3 × 5 = 15. 2 is 4 × 6 = 24. 3 is 2 × 4 = 8 wheels.