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What is LCM

1 year ago

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306 Replies

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6706 views

I

Iftikhar


please explain it briefly

306 Answers

M
Mathieu Daniel

LCM means Least Common multiple or factor. It is also the multiple of any two or more given integers. For example: LCM of 16 and 20 will be 2 X 2 X 2 X 2 X 5 = 80. Where 80 is the smallest common multiple for numbers 16 and 20.

J
Jess Jackson

LCM stands for Lowest Common Multiple. It’s the smallest positive integer that is divisible by two or more given numbers without leaving a remainder. Calculating the LCM is often useful in adding or subtracting fractions with different denominators.

R
RUTALI SANTOSHKUMAR AREKAR

LCM stands for "Least Common Multiple." It is the smallest positive integer that is a multiple of two or more numbers.

In other words, it is the smallest number that all the given numbers can divide into evenly.

The LCM is often used in various mathematical operations, such as adding or subtracting fractions with different denominators.

Usually fractions look scary and people often avoid them but using LCM you can make it simple and hence solve it easily.

E
Emmanuel Kwame

Least common multiple

J
Jeet

LCM is the short form for “Least Common Multiple.” The least common multiple is defined as the smallest multiple that two or more numbers have in common. For example: Take two integers, 2 and 3. Multiples of 2: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20.

F
Farwa

LCM is least common factor

R
Rishu

LCM is least common multiple. For example; LCM of 5 and 15 is 15.

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Lowest common multiple

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A
Alyssa Fernandes

Lowest common multiple, numbers are shared between 2 or more numbers eg. the lowest common multiple of 2 and 4 is 4

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LCM stands for lowest common multiple. We write out the multiplications for the numbers and then look for the first 'number' that appears in both lists. This is the LCM.

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LCM stands for the least common multiple or the lowest common multiple in math. The least common multiple of two or more numbers is the smallest number among all common multiples of the given numbers. Let's look at an example for a better understanding: let's look at 2 numbers: 3 and 7. Each has their own set of multiples:


Multiples of 3: 3, 6, 9, 12, 15, 18, 21, 24, 27,...

Multiples of 7: 7, 14, 21, 28, 35, 42,...


By looking at their multiples, we can notice that the first common multiple for 3 and 7 is 21. This is the least common multiple for 3 and 7. This is called the Listing Method which basically means listing a few multiples of each number until the lowest common multiple (LCM) is found. This method is used generally for low numbers where the LCM can be found only after a few listed multiples.


Another method available for finding LCM is by Prime Factorization Method, which is the most popular method as it is applicable for any number, low or high. The steps to be followed to use this method are the following:

  • Step 1: Find the prime factors of the given numbers by repeated division method.
  • Step 2: Write the numbers in their exponent form. Find the product of only those prime factors that have the highest power.
  • Step 3: The product of these factors with the highest powers is the LCM of the given numbers.


In order to understand better this method, let's look at an example:


Example: Find the least common multiple (LCM) of 50 and 120 using prime factorization.

Solution: Let us find the LCM of 50 and 120 using the prime factorization method.

  • Step 1: The prime factorization of 50 and 120 are: 50 = 2 × 5 × 5 and 120 = 2 × 2 × 2 × 3 × 5
  • Step 2: If we write these prime factors in their exponent form it will be expressed as 50 = 21 × 5 2  and

120 = 23 × 3 × 5

  • Step 3: Now, we will find the product of only those factors that have the highest powers among these. This will be: 23 × 31 × 52 = 8 × 3 × 25 = 600


Therefore, LCM of 50 and 120 is = 600.


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I
Ibtissem T

So, it is the lowest common multiple that two numbers share. For example, if I had 2 and 5 you would list out the multiples of each like so, 2,4,6,8,10,12,14 5,10,15,20,25 and recognise which number is the lowest that BOTH numbers have. In this case it would be 10!

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LCM stands for Lowest common multiple. It is the smallest number that divides evenly into the numbers given in the question. e.g the LCM of 10 and 15 would be 5.

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C
Callum Webb

LCM is a method where you have two or more numbers, and you fild the smallest number that can be multiplied into all of the numbers.


For example ; Q: Find the LCM of 20 and 25


So here, we could first try 2 as the LCM, however because 25 is odd we know that no even number can be a multiple.


Therefore the smallest number that can go into both 20 and 25 is 5.

5x4 = 20

5x5 = 25

U
Uchechukwu Asia

LCM is an acronym for Lowest Common Multiple. It is the least multiple that is common among two or more numbers.

For example, the LCM of 8 and 12 can be found as follows:

multiples of 8: 8, 16, 24, 32, 40, 48....

multiples of 12: 12, 24, 36, 48, 60....

It can be seen that the first number to appear as multiples in 8 and 12 is 24.


This is one method of finding the LCM. There is also another method known as the prime factorization method.

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