Last updated on May 26th, 2025
The LCM comes in use when we need to find a shared pattern between numbers that seem unrelated. We apply LCM to synchronize cycles or schedules, syncing digital signals and finding compatible frequencies in technology. In this article, we’ll take a look at the LCM of 2,3 and 7.
The LCM of 2,3 and 7 is the smallest positive integer that is a multiple of all the numbers. We find the LCM using the listing multiples method, the prime factorization method and the long division method.
The LCM of 2,3 and 7 can be found using the following steps:
Step 1: Write the multiples of each number
Multiples of 2 = 2,4,6,8,10,12,14,…42,…
Multiples of 3 = 3,6,9,12,18,…42
Multiples of 7 = 7,14,21,28,35,42,…
LCM(2,3,7) = 42
Step 2: Find the smallest multiple from the listed multiples
The smallest common multiple is 42.
Thus, LCM (2,3,7) = 42
The prime factors of each number are written, and then the highest power of the prime factors is multiplied to get the LCM.
Step 1:Find the prime factors of the numbers.
Prime factorization of 3 = 31
Prime factorization of 2 = 21
Prime factorization of 7 = 71
Step 2:Take the highest powers of each prime factor. Multiply the highest powers to get the LCM
LCM(2,3,7) = 42
It is not unusual that kids make mistakes when trying to find the LCM of the numbers 4,5 and 7.
This may be due to unclear understanding of the concept or confusion. Make sure to avoid these!
LCM (2,6,7) = LCM(2,3,7) → Verify.
LCM of 2,6,7;
Prime factorization of 2 = 21
Prime factorization of 6 = 21×31
Prime factorization of 7 = 71
LCM(2,6,7) = 42
LCM of 2,3,7;
Prime factorization of 3 = 31
Prime factorization of 2 = 21
Prime factorization of 7 = 71
LCM(2,3,7) = 42
LHS is equal to the RHS, the statement is true.
a=2, b=3, c=7. Verify using → LCM(a,b,c) = LCM(LCM(a,b),c)
LCM of 2,3;
Prime factorization of 3 = 31
Prime factorization of 2 = 21
LCM(2,3) = 6
Use the obtained LCM in the below;
LCM of 6,7;
Prime factorization of 6 = 21×31
Prime factorization of 7 = 71
LCM(6,7) = 42
LCM(2,3,7) =42, it verifies with the given formula.
Find x, LCM(3,9,x) = 72
We know that the LCM of 3,9 = 9
The prime factorization of 72 = 23×32
The LCM of 3,9 already includes 32, and the factor of x must include 23, which is 8.
By following the above assumption we assume that the value of x is 8.
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.
: She loves to read number jokes and games.