Operations with natural numbers.

 

Lesson 1.

OPERATIONS WITH NATURAL NUMBERS

Addition and subtraction with natural numbers.

Objective: To recognize and use natural numbers to solve mathematical operations in everyday life.

Keywords: Natural numbers, addition,subtraction,addends, product, minuend, subtrahend.

VOCABULARY 

N°	English	Spanish
1.	Addends	sumandos
2.	Adding	sumando
3.	Belong	pertenecer
4.	Counting	contar
5.	Difference	diferencia
6.	Equal	igual
7.	Following	siguiente
8.	Minuend	minuendo
9.	Product	producto
10.	Sum	suma
11.	Subtract	restar
12.	Subtrahend	sustraendo
13.	Sourt out	clasificar
14.	With out	sin

Lesson plan n°1 – English version

Lesson plan n°1 – Spanish version
What is a natural number?

Natural number is a part of the number system which includes all the positive integers from 1 to infinity. They are used for counting.

 It does not include zero (0).

But, when we combine 0 with a positive number such as 10, 20, etc. It becomes a natural number.

Number Line of Natural Numbers

Let’s learn about addition and subtraction with natural numbers.

Addition

Addition is taking two or more numbers and adding them together, that is to say, it is the total sum of 2 or more numbers.

For example:

And with elements or things is the same process      

Let’s see these examples:

Subtraction

To subtract means to take away from a group or a number of things. When we subtract, the number of things in the group is reduced or become less.

For example:

And with elements or things is the same process.

Let’s see these examples:

Let's watch the following video!

 Let's Practice!

According to this image, write the result of the operation.

Activity n° 1 

In the next activity, match the numbers that belong to the natural numbers.

Activity n° 2 

 

According to the number line, organize the natural numbers in the following activity.

Activity n° 3

Resolve the activities

Printed version activity

Properties of Addition

 Lesson 2.

Properties of addition 

Objective: To learn and recognize the properties of addition.

Key words: Number, addition, commutative property, associative property, neutral element.

Vocabulary

Nº	English	Spanish
1	Add	Sumar
2	Addens	Sumandos
3	Associative	Asociativa
4	Commutative	Conmutativa
5	Element neutral	Elemento neutro
6	Empty	Vacío
7	Equal	Igual
8	Left-to-right	De izquierda a derecha
9	Oatmeal	Avena
10	Perform	Realizar
11	Property	Propiedad
12	Solve	Resolver
13	Sum	Suma
14	To find out	Descrubir/saber

Lesson Plan Nº2 - English version 

Lesson Plan Nº2 - Spanish version 

Let’s learn!

The properties of addition will help you to better understand this operation. Moreover, in some cases they will serve to simplify your calculations.

Remember, the sum has three properties. The properties are commutative, associative, and neutral element.

 

1. Commutative property: When two numbers are added, the result is the same regardless of the order of the addends. For example:

 8 + 4 = 12

And

4 + 8= 12

As you can see, the result is the same.

 

2. Associative Property: When three or more numbers are added, the result is the same regardless of the order in which the addends are added. For example, if we must do the sum

9 + 4 + 6

The associative property assures that we can perform this operation in two different ways obtaining the same result, let's see:

ü  The first way is:

(9 + 4) + 6

In this case, the parentheses tells that we must first add the numbers (9 + 4), then, the result of this sum is operated with the third number, 13 + 6

 This is the complete operation:

9 + 4 + 6 = (9 + 4) + 6

= 13 + 6

= 19

ü  The second way is:

9 + (4 + 6)

Now, the parentheses tell that we must first perform the sum (4 + 6), once this is done, we can do the sum of the first number with the result obtained in the parentheses, 

10 + 9

Look at the complete operation:

9 + 4 + 6 = 9 + (4 + 6)

= 10 + 9

= 19

As you can see, when applying the two forms we obtain the same result, 19. This does not happen only with these numbers but also with all.

 

3. Neutral element: This property is particular since it assures that there is a particular number that does not affect the others when the addition is made, and it is the number 0. Let's check!

The sum of any number and zero is equal to the original number.

 For example: 7 + 0 = 7.

Let's watch the following video!

Since the way to carry out the sum operation is already clear, we can use it to solve everyday situations. Below we will find some exercises in order to put into practice what you have learned.

Let's practice!

Activity nº1

Fill in the missing numbers.

Activity nº2

Choose the correct option about addition properties.

Activity nº3

Choose the correct option.