What is the LCM of 3 and 7?
The least common multiple of 3 and 7 is the least number which is exactly divisible by both 3 and 7
Answer: LCM of 3 and 7 is 21
Lets see how to find the LCM of 3 and 7
The Least Common Multiple (LCM) of two numbers a and b is the smallest number that divides a and b exactly.
We can find the LCM of the numbers in many ways.
Methods to Find LCM of 3 and 7
Let us use the following methods to find the LCM of 3 and 7
- Listing the Multiples
- Common Division
Find LCM of 3 and 7 by Listing Method
We list the first few multiples of 3 and 7 and then identify the common multiples of 3 and 7
The least among the common multiples is the LCM of 3 and 7
Find LCM of 3 and 7 by Common Division Method
Follow the steps mentioned below to find the LCM of 3 and 7 by the common division method.
- Step 1: Write the numbers 3 and 7 horizontally by separating them with a comma.
- Step 2: Choose the smallest prime number that divides at least any one of them.
- Step 3: Write the quotient in the next row just below the numbers. If any of the numbers are not divided, we will bring it down directly.
- Step 4: We will stop it when we don't have a prime number to divide the given numbers.
- Step 5: Least common multiple of 3 and 7 will be the product of primes by which we have divided.
So, using the common division method, LCM of 3 and 7 is 21
Irrespective of the method, the solution to our question LCM of 3 and 7 is the same.