243 LearnersLast updated on May 26th, 2025
LCM of 5 and 15
LCM is a common multiple, the smallest value between the numbers 5 and 15. Did you know? We apply LCM unknowingly in everyday situations like setting alarms and to synchronize traffic lights and when making music.
How to find the LCM of 5 and 15
The LCM of 5 and 15 is 15. We can find the LCM using the Listing multiples method, the prime factorization method and the long division method. These are explained below.
Struggling with Math?
Get 1:1 Coaching to Boost Grades Fast !
LCM of 5 and 15 using the Listing Multiples Method
Step 1: Write down the multiples of the numbers. Don’t stop too early.
— Multiples of 5 = 5,10,15,20,25,30,…
— Multiples of 15 = 15,15,45,60,75,…
Step 1: Find the smallest number common between the written multiples of 5, 15.
— The smallest common multiple is 15
Thus, LCM(5,15) = 15
LCM of 5 and 15 using the Prime Factorization Method
Step 1: factorize the numbers into its prime factors
5 = 5×1
15 = 5×3
Step 2: find the highest powers of the factors of 5 and 15
Step 2: Multiply the highest powers
LCM(5,15) = 15
LCM of 5 and 15 using the Division Method
- Write the numbers 5,15 in a row
- Divide them by their common prime factors, if there is one
- Carry forward the numbers that are left undivided by the previously chosen factor
- Continue dividing until the remainder is ‘1’
- Multiply the divisors to find the LCM
- LCM(5,15) = 15
Common Mistakes and how to avoid them while finding the LCM of 5 and 15
Listed here are a few mistakes that one can commit when trying to find the LCM of the numbers 5 and 15. Try to avoid them.
Mistake 1
Listing incorrect multiples
If the LCM of given numbers is 15, double-check that the number appears on the list of both 5 and 15
Mistake 2
Prime factorization errors
Check if the numbers are prime factored correctly. For example, we may accidentally write 15 = 5×2 instead of 15 = 5×3.
Mistake 3
Thinking product is the LCM
One may think the product of the numbers is the LCM of the numbers. This is only true in case of co-prime numbers.
Level Up with a Math Certification!
2X Faster Learning (Grades 1-12)
LCM of 5 and 15, examples
Problem 1
The LCM of two numbers is 15, and one number is 5, what percentage of the LCM is 5?
Percentage = Number/LCM×100
Percentage = 5/15×100=33.33%
Explanation
Thus, 5 is 33.33% of the LCM.
Problem 2
If the LCM of 5 and a number xxx is 15, what is xxx?
The LCM(5, x) = 15. Since the prime factorization of 15 is 31.×51, and the LCM must include both the 3 and the 5,x must be 15.
Explanation
The missing number must contribute the factors that 5 doesn’t have to make the LCM 15.
Problem 3
If the LCM of 5 and 15 is increased by 50%, what is the new value?
LCM(5, 15) = 15.
50% increase = 50/100×15=7.5
New value = 15 + 7.5 = 22.5.
Explanation
A percentage increase involves multiplying the original value by the percentage and adding the result back to the original.
Turn your child into a math star!
#1 Math Hack Schools Won't Teach!
FAQs on LCM of 5 and 15
1.What is the LCM of 5,10 and 15?
2.What are the common factors of 3 and 5?
3.What are the common factors of 5 and 12 ?
4.What is the LCM of 12 and 15?
5.What is the LCM of 5 and 25 ?
6.How can children in Vietnam use numbers in everyday life to understand LCM of 5 and 15?
7.What are some fun ways kids in Vietnam can practice LCM of 5 and 15 with numbers?
8.What role do numbers and LCM of 5 and 15 play in helping children in Vietnam develop problem-solving skills?
9.How can families in Vietnam create number-rich environments to improve LCM of 5 and 15 skills?
Struggling with Math?
Get 1:1 Coaching to Boost Grades Fast !
Important glossaries on the LCM of 5 and 15
- Multiple — product of a number and a natural integer
- Prime factor — number one gets after prime factorization any given number
- Prime factorization — the process of breaking the number into its prime factors.
Explore More numbers
![Important Math Links Icon]()
Previous to LCM of 5 and 15
About BrightChamps in Vietnam
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.
