Mastering Divisibility Rules for 2 - 15: What You Need To Know By: Teacher Virgie

    

Mastering Divisibility Rules for 2 - 15: What You Need To Know

DIVISIBILITY RULES

By: Teacher Virgie

         Understanding divisibility rules is like having a secret code to unlock the mysteries of numbers. These rules provide a shortcut to determine if a number is divisible by another without the need for complex calculations. In this blog, we'll delve into the fascinating world of divisibility rules, demystifying the process and showcasing how these rules can simplify your mathematical journey.

   Let us now explore the different divisibility rules/tests! You may notice some similarities among the rules.

Divisibility by 2: The Rule of Evenness

• Any number ending in 0, 2, 4, 6, or 8 is divisible by 2.

Examples: 
34              

46              

98              

200            

502

Divisibility by 3: The Sum Rule

• The sum of a number's digits determines its divisibility by 3.

Examples: 
39 = 3 + 9 = 12, so 39 is divisible by 3

1563 = 1 + 5 + 6 + 3 = 15, so 1563 is divisible by 3

Divisibility by 4: The Last Two Digits Rule

• If the last two digits of a number are divisible by 4, the entire number is divisible by 4.

Example: 
4564

64 is the last digit and it's divisible by 4 and 4564 is divisible by 4.

Divisibility by 5: The Ending in 0 or 5 Rule

• Any number ending in 0 or 5 is divisible by 5.

Examples: 
205              

380           

200            

505          

1440

Divisibility by 6: The Combination Rule

• If a number is divisible by both 2 and 3, it is divisible by 6.

Example: 
504

The last digit of 504 is 4, so it's divisible by 2.

Find the sum of all digits of 504 if it is divisible by 3. 

5 + 0 + 4 = 9 and 9 is divisible by 3.

Since both divisible by 2 and 3; therefore 504 is divisible by 6.

Divisibility by 9: The Sum Rule Revisited

• Similar to divisibility by 3, the sum of a number's digits determines its divisibility by 9.

Examples: 
1539 = 1 + 5 + 3 + 9  = 18, so 1539 is divisible by 9

8964 = 8 + 9 + 6 + 4 = 27, so 8964 is divisible by 9

Divisibility by 10: The Ending in 0 Rule

• Any number ending in 0 is divisible by 10.

Examples: 
200              

380           

200            

500          

1440

Divisibility by 11: Difference between The Alternating Sums Rule

• Difference between the alternating sums of a number's digits determines its divisibility by 11.

Example: 
17490

Find the alternating sum of a number's digits starting from right to left

1 + 4 + 0 = 5

7 + 9 = 16

16 - 5 = 11

Hence, 17490 is divisible by 11.

Divisibility by 12: The Combination of 3 and 4

• If a number is divisible by both 3 and 4, it is divisible by 12. 

Divisibility by 14: The Combination of 2 and 7

• If a number is divisible by both 2 and 7, it is divisible by 14. 

Divisibility by 15: The Combination of 3 and 5

• If a number is divisible by both 3 and 5, it is divisible by 15. 

      Mastering divisibility rules is like having a powerful toolkit for navigating the world of numbers. By understanding and applying these rules, you not only simplify mathematical calculations but also develop a deeper appreciation for the inherent patterns and logic within the realm of mathematics. So, embrace the divisibility rules, unlock the secrets of numbers, and elevate your math prowess to new heights!

WORKSHEET ON DIVISIBILITY RULES

BY: TEACHER VIRGIE

ANSWER KEY

BY: TEACHER VIRGIE

Leave  a comment if you have any questions. 

Thank you.

 PROPERTIES OF MULTIPLICATION

for Primary Mathematics

By: Teacher Virgie

    Studying the properties of multiplication is important because it helps us understand how multiplication works and how we can use it to solve problems more efficiently. There are several properties of multiplication, including the commutative, associative, and distributive properties.

1. The commutative property tells us that the order of the factors doesn't affect the product. 

For example, 3 x 2 is the same as 2 x 3. 

This property is useful because it allows us to rearrange the factors in a multiplication problem without changing the answer.

2. The associative property tells us that the grouping of the factors doesn't affect the product. 

For example, (5 x 2) x 3 is the same as 5 x (2 x 3). 

This property is useful because it allows us to group the factors in a way that makes the problem easier to solve.

3. The distributive property tells us that we can break up a multiplication problem into smaller parts and then add the products together. 

For example, 2 x (3 + 4) is the same as (2 x 3) + (2 x 4). 

This property is useful because it allows us to simplify complex multiplication problems.

4. The zero property tells us any number multiply by zero is always zero.

For example, 15 x 0 is equal to 0 or

0 x 15 = 0

5. The identity property of multiplication tells us that any number multiply by 1, the answer is always the number itself.

For examples:

20 x 1 = 20

100 x 1 = 100

2255 x 1 = 2255

By understanding the properties of multiplication, you can become more efficient problem solvers and better understand the relationships between numbers.

Let's practice!

Name the multiplication property that is shown by each equation. You may write commutative, associative, distributive, zero or identity.

1.) 0 x 12 = 0    ______________

2.) 1 x 76 = 76 ______________

3.) 5 x (6 + 4) = (5 x 6) + (5 x 4) ______________

4.) 6 x 8 = 8 x 6 ______________

5.) 11 x (10 x 9) = (11 x 10) x 9 ______________

Answer:

1. zero 2. identity 3. distributive 4. commutative 5. associative

By understanding the properties of multiplication, you can become more efficient problem solvers and better understand the relationships between numbers.

How about this? What is the missing number that will make an equation true?

15 x (8 + 1) = (15 x _____) + (15 x 1)

Comment the answer below!!! 

Fraction Chart

    

FRACTION CHART 

FOR PRIMARY OR GRADE SCHOOL MATH

By: Teacher Virgie

    Fraction charts are useful tools that can be used for a variety of purposes. One of the primary purposes of a fraction chart is to provide a visual representation of fractions and their relationships to one another. This can be helpful for students who are just beginning to learn about fractions, as it can make it easier for them to understand the concepts.

    Another purpose of a fraction chart is to help with fraction operations, such as adding, subtracting, multiplying, and dividing fractions. By using a fraction chart, students can more easily see how fractions are related and how they can be manipulated to solve problems.

    Fraction charts can also be used as a reference tool for students who need to quickly look up the decimal or percentage equivalent of a fraction. This can be helpful for students who are working on math problems that require them to convert between fractions, decimals, and percentages.

    Overall, fraction charts are versatile tools that can be used in a variety of ways to help students better understand and work with fractions.