Grade 4 ↓
Multiplication and Division
Introduction
Multiplication and division are two of the four basic operations in mathematics, the others being addition and subtraction. These operations are used to solve problems involving equal grouping and sharing. Understanding these concepts will enable students to solve real-world problems more effectively.
Understanding multiplication
Multiplication is a method of adding faster. For example, if you have 3 baskets with 4 apples in each basket, instead of adding 4 apples three times (4 + 4 + 4
), you can multiply the number of baskets (3) by the number of apples in each basket (4). So, 3 x 4
equals 12, which tells you there are 12 apples total.
4 + 4 + 4 = 12 (Addition) 3 x 4 = 12 (multiplication)
Visual example of multiplication
This image shows 3 columns, each column containing 2 boxes. You can see how 3 x 2 = 6
is represented.
Simple text examples of multiplication
Let's look at some more examples:
- If you have 5 piles of books and each pile has 2 books, you will have a total of
5 x 2 = 10
books. - If there are 4 cars, and each car has 4 wheels, then there will be a total of
4 x 4 = 16
wheels. - There are 7 days in a week. If you think of 3 weeks, you can multiply to find the number of days:
7 x 3 = 21
days.
Understanding partitioning
Division is the process of making equal groups from a number. It is the opposite of multiplication. For example, if you have 12 candies and you want to divide them equally among 3 friends, you can find out how many candies each friend will get by dividing 12 by 3. 12 ÷ 3 = 4
means each friend will get 4 candies.
Divide 12 candies into 3 equal groups = 4 candies/group 12 ÷ 3 = 4
Visual example of partitioning
In this picture, 12 candies are divided among three friends. Each group gets 4 candies.
Simple text examples of division
Here are some segmentation examples:
- If you have 16 apples and want to give 4 apples to each friend, you can determine how many friends will get apples:
16 ÷ 4 = 4
. - You have 20 balloons, and you put them in bags containing 5 balloons each. The number of bags is
20 ÷ 5 = 4
. - If there are 81 players and you want to make a team of 9, the number of teams you can make is
81 ÷ 9 = 9
.
Relationship between multiplication and division
Multiplication and division are very closely related operations. If you know how one works, you can understand the other. For example, if you know that 3 x 4 = 12
, you also know that 12 ÷ 3 = 4
and 12 ÷ 4 = 3
. This relationship helps you check your work and solve problems faster.
Using examples
To see this relationship, consider these examples:
Multiplication: 6 x 5 = 30 Related divisions: 30 ÷ 5 = 6 or 30 ÷ 6 = 5
In this example, we are multiplying to find that 6 groups of 5 make 30. Then, we use division by dividing 30 into equal groups to confirm how many we have (6) or how big the groups were (5).
Let's look at another example:
Multiplication: 7 x 8 = 56 Related divisions: 56 ÷ 8 = 7 or 56 ÷ 7 = 8
Properties of multiplication
It can be really helpful to learn some properties of multiplication:
- Commutative Property: The order of the numbers does not affect the result. For example,
4 x 5 = 5 x 4 = 20
. - Associative Property: When you multiply three or more numbers, the way you group them does not change the result. For example,
(2 x 3) x 4 = 2 x (3 x 4) = 24
. - Distributive Property: You can make numbers easier to work with by breaking them up. For example:
4 x (3 + 5) = (4 x 3) + (4 x 5) = 12 + 20 = 32
. - Identity Property: One times any number is that number. For example,
7 x 1 = 7
. - Zero Property: Any number multiplied by zero equals zero. For example,
9 x 0 = 0
.
Properties of division
Division also has some properties, although less than multiplication:
- Division by one: Any number divided by one is itself. For example,
8 ÷ 1 = 8
. - Division by zero: Division by zero is not possible. It is undefined.
Use of multiplication and division in real life
Multiplication and division aren't just for school. They're useful in everyday life, too. Here are some examples:
- Shopping: When buying multiple items with the same price, use multiplication to find the total cost.
- Cooking: If you are planning to make smaller meals then it is important to divide the ingredients in the recipes according to the number of servings.
- Sharing: Whether it's splitting a pizza among friends or distributing candy, division is important.
- Building projects: Understand measurements and quantities using multiplication for material calculations.
Practice problems
To practice your understanding, try solving these problems:
- You have 7 bags. Each bag contains 6 marbles. How many marbles do you have in total?
(7 x 6 = ?)
- There are 24 cookies, and you want to divide them equally into 6 boxes. How many cookies will be in each box?
(24 ÷ 6 = ?)
- A garden is divided into 9 equal parts, each part has 5 flowers. How many flowers are there?
(9 x 5 = ?)
- If you want to distribute 36 stickers equally among 4 friends, how many stickers will each friend get?
(36 ÷ 4 = ?)
Conclusion
Mastering multiplication and division allows you to solve problems more efficiently, whether dealing with numbers in class or tasks outside of school. By practicing these operations and their properties, you build a strong foundation for learning math in the future. Practice regularly to turn these skills into second nature.