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What is LCM

1 year ago

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321 Replies

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I

Iftikhar


please explain it briefly

321 Answers

Baoji L Profile Picture
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LCM stands for the lowest common multiple, for two or more numbers. The LCM of a and b is the smallest number that is divisble by both a and b. For example, the LCM of 4 and 10 is 20, as 20 is the lowest number that is divisible by both 4 and 10.

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Yumna H Profile Picture
Yumna H Verified Sherpa Tutor ✓

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LCM is the lowest common multiple. Let's go step by step:

What does multiple mean?

This is jut basically the multiplication tables.

For example:

The multiples of 3 is 3, 6, 9, 12, 15, 18, 21, 24, 27

Multiples of 4 is 4, 8, 12, 16, 20, 24


So now back to the question. Say they ask you a question like this:

What is the LCM of 4 and 3?

First we write the multiples of 4 and 3 which is:

4 8 12 16 20 24 28 32

3 6 9 12 15 18 21 24 27


now we compare both the multiples and find what the common multiples are.

above you can see that 12 and 24 are common. But since LCM means the "lowest" common multiple, we have to select the lowest number which is 12.

12 is the LCM of 4 and 3.


Basically LCM is just writing down the multiples and then selecting the lowest common multiple between the numbers.


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M
Monika Chaulagain

Lowest common multiple.

L
Linda C

LCM stands for Lowest Common Multiple. This means the smallest number that is in the times tables of a set of numbers. Eg.


What is the LCM of 5 and 14?


Write out the multiples of 5 and the multiples of 14 :


5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75


14, 28, 42, 56, 70, 84, 96


The smallest number that is in both is 70 so the LCM of 5 and 14 is 70.


I hope that helps.


As you practice more you will find shortcuts. In this example, if you had written the multiples of 14 first you should have been able to find the LCM without writing out the multiples of 5. How? All multiples of 5 end in 0 or 5. And the first multiple of 14 that meets that criteria is 70!


M
Melissa K

This is the Lowest Common Multiple

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

H
Hannah Totman

The answer is Least Common multiple.


The LCM of two or more numbers is the smallest number that is evenly divisible by all numbers in the set.


For example:


By prime factorisation method, we can write 8 and 10 as the product of prime numbers, such that;

8 = 2 × 2 × 2 

10 = 2 × 5

LCM (8, 10) = 2 × 2 × 2 × 5 = 40


Sarrey H Profile Picture
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LCM stands for Lowest Common Multiple for two or more numbers in Maths. For example, to find the LCM of number 6 and 4, we can

step1: write down the multiples of each number from the smallest onwards

step2: find out the first number that is a multiple of both numbers


So you working will be like this:

Multiples of 4: 4, 8, 12, 16, 20, 24...

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


As you can see, numbers 12, 24 and propably more if we write down more occured in above lists and they are all the common multiples of 4 and 6. Among all these, 12 is the smallest or lowest, so

12 is the lowest Common Multiple of 4 and 6, that is to say

LCM of 4 and 6 = 12



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Abdul R Profile Picture
Abdul R Verified Sherpa Tutor ✓

Masters graduate in Chemical Engineering

LCM stands for Lowest Common Multiple


For example,


Question: What is the lowest common multiple between (LCM) between 6 and 10 ?


Answer: 30


Explanation:

you have to find a number that is a multiple of 6 and 10 but it has to be a multiple of the two and the lowest value possible. So,


6 x 1 = 6 10 x 1 = 10

6 x 2 = 12 10 x 2 = 20

6 x 3 = 18 10 x 3 = 30

6 x 4 = 24 10 x 4 = 40

6 x 5 = 30 10 x 5 = 50


From the timestable you can see that 30 is the lowest common multiple between 6 and 10. 60 is also a multiple if you continue the timestable but that is not the lowest value. Therefore, its important you always take the lowest value



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Abdullah T Profile Picture
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LCM stands for Lowest Common Multiple. This consists of finding a common number multiplied a certain times for two numbers.

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A
Atul Sharma

LCM stands for Lowest Common Multiple.

Let's say you have two numbers (n1,n2) and you want to find out what is the lowest number (LCM) which is multiple of both of our numbers (n1,n2). This smallest number is called LCM of our numbers (n1,n2).


For e.g.,

Suppose our two numbers are 10 and 15.

Method to get LCM:

Step 1: Get prime factors of your numbers.

Factors of 10 are : 2,5

Factors of 15 are: 3,5


Step 2: Multiply all the prime factors. (NOTE: Do not repeat any prime factor if it has already been considered).


LCM= 2*3*5 (NOTE: 5 was only considered once and not repeated twice)

=30

Jennie K Profile Picture
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LCM stands for the LOWEST COMMON MULTIPLE.


It means the lowest number in the timetables you are looking at.


For example, the LCM of 4 and 6 is 12 because:


4 timestable : 4, 8, 12, 16, 20, 24,28,32..

6 timestable : 6,12,18,24,30,36,...


You can see the lowest multiple is 12. You can probably see 24 in both too. 24 is simply a multiple of 4 and 6, not the lowest common multiple.


Hope that helps :)



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F
Folasayo Emmanuel Ogundipe

The LCM simply means Least Common Multiple.


Multiply the list of prime factors together to find the LCM.

...

For example, for LCM (12,30) we find:

  1. Prime factorization of 12 = 2 × 2 × 3.
  2. Prime factorization of 30 = 2 × 3 × 5.
  3. Using all prime numbers found as often as each occurs most often we take 2 × 2 × 3 × 5 = 60.
  4. Therefore LCM (12,30) = 60.


H
Hoor Ul Ain

LCM stands for least common factor thats mean we have to found the most least amount used in whole proplem

S
Sahar Jokar

LCM is least common multiple .for example LCM of 5 and 15 is 15 . If you observe the common multiples of 5 and 15 , there are 15, 30 , 45 and so on

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