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What is LCM

1 year ago

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327 Replies

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I

Iftikhar


please explain it briefly

327 Answers

R
Rihan K

LCM stands for Least Common Multiple. The least common multiple of two or more numbers is the smallest positive number that is divisible by each of those numbers.

Some key properties of LCM:

  • The LCM of two numbers contains all the prime factors common to both numbers
  • To find the LCM, find all the prime factors of each number and multiply together the highest powers of each prime factor
  • The LCM of a set of numbers is the smallest number (not zero) that can be evenly divided by each number in the set
  • The LCM of two numbers can be calculated using the formula: LCM(a,b) = (a*b) / GCD(a,b), where GCD is the greatest common divisor

Some examples:

  • LCM(2,3) = 6 (factors are 2, 3)
  • LCM(2,8) = 8 (factors are 2, 2, 2)
  • LCM(5,10,15) = 30 (factors are 5, 2, 3)

The LCM has many practical applications from figuring out lowest common denominators to combining rhythms in music composition. Understanding the concept of LCM is foundational for higher math and useful across many disciplines.

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LCM stands for "Least Common Multiple." It helps us find the smallest number, that is a multiple of two or more other numbers. Let's use some examples:


Example 1: Let's say you have two numbers, 4 and 6. We want to find the LCM of these two numbers.


First, we list the multiples of each number:

- Multiples of 4: 4, 8, 12, 16, 20, ...

- Multiples of 6: 6, 12, 18, 24, 30, ...


Now, we look for the smallest number that appears in both lists. In this case, 12 is the smallest number that is a multiple of both 4 and 6. So, the LCM of 4 and 6 is 12.


Example 2: Let's try three numbers this time: 3, 5, and 7.


First, we list the multiples of each number:

- Multiples of 3: 3, 6, 9, 12, 15, ...

- Multiples of 5: 5, 10, 15, 20, 25, ...

- Multiples of 7: 7, 14, 21, 28, 35, ...


Now, we look for the smallest number that appears in all three lists. In this case, 15 is the smallest number that is a multiple of 3, 5, and 7. So, the LCM of 3, 5, and 7 is 15.


The LCM helps us when we need to do things like adding or subtracting fractions with different denominators or solving problems involving multiple numbers. 

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LCM stands for “Least Common Multiple”, for example, the LCM, or Least common multiple of 6 and 9 is 18.

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Ms Binny Bahanda

This answer refers to the “lowest common multiple”. This is the lowest times table in common with all of the numbers relating to the question.

S
Sharmarke

lowest common multiple

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LCM stands for "Lowest Common Multiple" which means the smallest multiple that can be evenly divided by the given whole numbers (integers).


Here's a basic example:

Let's find the Lowest Common Multiple of 12 and 18:


List the multiples of each number:

  • Multiples of 12: 12, 24, 36, 48, ...
  • Multiples of 18: 18, 36, 54, 72, ...


Find the smallest common multiple in the lists, which is 36 (number in both 12 and 18 times tables).

So, the LCM of 12 and 18 is 36.


I hope this helps!

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LCM stands for "Least Common Multiple" in math. It is a fundamental concept used in arithmetic and number theory. The LCM of two or more numbers is the smallest multiple that is divisible by each of those numbers without leaving a remainder.

Here are the key points to understand about LCM:

  1. Definition: The LCM of two or more integers is the smallest positive integer that is divisible by each of the given integers without any remainder.
  2. Notation: The LCM of two numbers �
  3. a and �
  4. b is often written as LCM(�,�
  5. a,b), or sometimes as LCM(�,�)
  6. LCM(a,b) or LCM[�,�]
  7. LCM[a,b].
  8. Example: Let's find the LCM of 4 and 6. First, list the multiples of each number:
  • Multiples of 4: 4, 8, 12, 16, 20, ...
  • Multiples of 6: 6, 12, 18, 24, 30, ...
  1. The smallest number that appears in both lists is 12. So, LCM(4, 6) = 12.
  2. LCM of More than Two Numbers: You can find the LCM of more than two numbers by finding the LCM of pairs of numbers successively. For example, to find the LCM of 4, 6, and 8, you can find LCM(4, 6) first (which is 12), and then find LCM(12, 8), which is 24. So, LCM(4, 6, 8) = 24.
  3. Applications: LCM is used in various mathematical and real-world applications, such as simplifying fractions, finding a common denominator for adding or subtracting fractions, solving problems involving periodic events or cycles, and more.
  4. GCD vs. LCM: LCM is closely related to another important concept called the Greatest Common Divisor (GCD) or Greatest Common Factor (GCF). While LCM deals with finding a common multiple, GCD focuses on finding the largest common factor/divisor of two or more numbers. These two concepts are often used together in various mathematical problems.

In summary, the LCM is a mathematical concept used to find the smallest multiple that is evenly divisible by a set of numbers, making it a valuable tool in various mathematical calculations and problem-solving scenarios.

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S
Shahriar Alam

This stands for lowest common multiple for 2 numbers, for example the LCM of 5 and 6 would be 30 as this is the smallest number that is divisible by both 5 and 6.

R
Rosie

LCM stands for "Least Common Multiple." In mathematics, it refers to the smallest multiple that two or more numbers have in common. For example, the LCM of 4 and 6 is 12, because it's the smallest number that both 4 and 6 divide evenly into. Hope this helps !

C
Celissia Ehiwarior

LCM means the lowest common multiple. The lcm is the smallest multiple that two or more numbers share. It is the smallest number that can be divided by each of the given numbers without leaving a remainder. For example the lcm of 4 and 6 is 12 because it’s the smallest number that both 4 and 6 can go into without leaving any remainders and evenly divides.


A
Ashan Bala

An LCM is known as the Lowest Common Multiple. You are normally asked the Lowest Common Multiple of 2 or more numbers. If you wrote the times tables of these 2 numbers individually, it is the lowest number on both of the times tables lists.

E
Emmanuel Kwame

Least common multiple

C
Charlotte Barber

The LCM stands for Lowest Common Multiple and it is the smallest number that two or more numbers can divide into evenly, as whole numbers.

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LCM is lowest Common Multiple. For example we are evaluating LCM of 15 and 20. We need to make a list of common multiples for both the numbers and identify which is lowest and common at the same time. Hope this helps.

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M
Mrs Bibi

Least Common Multiple 

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