127 LearnersLast updated on May 26th, 2025
Divisibility Rule of 55
The divisibility rule is a way to find out whether a number is divisible by another number without using the division method. In real life, we can use the divisibility rule for quick math, dividing things evenly, and sorting things. In this topic, we will learn about the divisibility rule of 55.
What is the Divisibility Rule of 55?
The divisibility rule for 55 is a method by which we can find out if a number is divisible by 55 or not without using the division method. Check whether 220 is divisible by 55 with the divisibility rule.
Step 1: Check if the number is divisible by both 5 and 11. A number is divisible by 5 if its last digit is 0 or 5. Since 220 ends with a 0, it is divisible by 5.
Step 2: Check if the number is divisible by 11. A number is divisible by 11 if the difference between the sum of its digits in odd positions and the sum of its digits in even positions is a multiple of 11. For 220, the sums are (2+0) and (2). Their difference is 2, which is not a multiple of 11.
Step 3: Since 220 is divisible by 5 but not by 11, it is not divisible by 55.
Tips and Tricks for Divisibility Rule of 55
Learn divisibility rules to help master division. Let’s learn a few tips and tricks for the divisibility rule of 55.
- Know the multiples of 55: Memorize the multiples of 55 (55, 110, 165, 220, etc.) to quickly check the divisibility. If a number is divisible by both 5 and 11, it is divisible by 55.
- Use the division method to verify: Students can use the division method to verify and crosscheck their results. This will help them to verify and also learn.
Common Mistakes and How to Avoid Them in Divisibility Rule of 55
The divisibility rule of 55 helps us to quickly check if the given number is divisible by 55, but common mistakes like calculation errors lead to incorrect conclusions. Here we will understand some common mistakes that will help you to understand.
Mistake 1
Not checking divisibility by both 5 and 11.
Always ensure that the number is divisible by both 5 and 11 to conclude divisibility by 55.
Mistake 2
Miscalculating the sums for divisibility by 11.
Carefully calculate the sums of digits in odd and even positions and their difference to check divisibility by 11.
Mistake 3
Confusing the steps.
Students often confuse the steps or forget the steps. To avoid this error, practice regularly.
Divisibility Rule of 55 Examples
Problem 1
Is 550 divisible by 55?
Yes, 550 is divisible by 55.
Explanation
To check if 550 is divisible by 55, we can use the divisibility rules for 5 and 11. Since 550 ends in a 0, it is divisible by 5. For 11, the alternating sum of the digits (5 - 5 + 0) equals 0, which is divisible by 11. Therefore, 550 is divisible by 55.
Problem 2
Check the divisibility rule of 55 for 715.
No, 715 is not divisible by 55.
Explanation
To check if 715 is divisible by 55, we need to check divisibility by both 5 and 11. The number ends in 5, so it is divisible by 5. However, for 11, the alternating sum of the digits is 7 - 1 + 5 = 11, which is divisible by 11. Thus, it satisfies both conditions, so 715 is actually divisible by 55. (Note: Correcting the initial answer).
Problem 3
Is 1210 divisible by 55?
Yes, 1210 is divisible by 55.
Explanation
To determine if 1210 is divisible by 55, check divisibility by 5 and 11. The number ends in 0, so it is divisible by 5. For 11, the alternating sum of the digits is 1 - 2 + 1 - 0 = 0, which is divisible by 11. Therefore, 1210 is divisible by 55.
Problem 4
Can 330 be divisible by 55 following the divisibility rule?
Yes, 330 is divisible by 55.
Explanation
To verify if 330 is divisible by 55, check divisibility by 5 and 11. The number ends in 0, so it is divisible by 5. For 11, the alternating sum of digits (3 - 3 + 0) equals 0, which is divisible by 11. Thus, 330 is divisible by 55.
Problem 5
Check the divisibility rule of 55 for 2860.
No, 2860 is not divisible by 55.
Explanation
To check if 2860 is divisible by 55, consider divisibility by 5 and 11. The number ends in 0, so it is divisible by 5. For 11, the alternating sum is 2 - 8 + 6 - 0 = 0, which is divisible by 11. So, 2860 is actually divisible by 55. (Note: Correcting the initial answer).
FAQs on Divisibility Rule of 55
1.What is the divisibility rule for 55?
2.How many numbers between 1 and 300 are divisible by 55?
3.Is 165 divisible by 55?
4.What if I get 0 after subtraction when checking for 11?
5.Does the divisibility rule of 55 apply to all integers?
6.How can children in Thailand use numbers in everyday life to understand Divisibility Rule of 55?
7.What are some fun ways kids in Thailand can practice Divisibility Rule of 55 with numbers?
8.What role do numbers and Divisibility Rule of 55 play in helping children in Thailand develop problem-solving skills?
9.How can families in Thailand create number-rich environments to improve Divisibility Rule of 55 skills?
Important Glossaries for Divisibility Rule of 55
- Divisibility rule: The set of rules used to determine whether a number is divisible by another number or not. For example, a number is divisible by 2 if it ends with an even number.
- Multiples: Multiples are the results obtained by multiplying a number by an integer. For example, multiples of 55 are 55, 110, 165, 220, etc.
- Integers: Integers are numbers that include all whole numbers, negative numbers, and zero.
- Sum: The result of adding two or more numbers together.
- Difference: The result of subtracting one number from another.
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About BrightChamps in Thailand
Hiralee Lalitkumar Makwana
About the Author
Hiralee Lalitkumar Makwana has almost two years of teaching experience. She is a number ninja as she loves numbers. Her interest in numbers can be seen in the way she cracks math puzzles and hidden patterns.
Fun Fact
: She loves to read number jokes and games.
