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Question

What is LCM

2 years ago

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409 Replies

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10789 views

I

Iftikhar


please explain it briefly

409 Answers

F
Farooq

LCM is the abbreviation for the Least Common multiple, which refers to the smallest number that is dividable by both two numbers or all the numbers for more than two numbers.

M
Mohamed Sharif-Eidarus

Lowest Common Multiple


Given some numbers, could be 2 or more, we need to find the smallest number that is a multiple of all the numbers in your list.


For example -


1) 10 and 15

The lowest common multiple is 30 since, 30 is a multiple of both 10 (i.e. 10 x 3 = 30) and 15 (i.e. 15 x 2 = 30).


2) 6, 8 and 14

The lowest common multiple is 168 since, 168 is a multiple of both 10 (i.e. 6 x 28 = 168), 15 (i.e. 8 x 21 = 168) and 14 (i.e. 14 x 12 = 168).


There is three popular ways of finding this number:


1) Exhaustive method. Make a list of all the multiples of all numbers and find the first common multiple.

2) Finding the prime factors of the all numbers and with that you can find your answer. (You need a whole lesson to understand this)

3) Venn diagram method. (You need a whole lesson to understand this)

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The lowest common multiple (LCM) is the lowest multiple shared by two or more numbers.

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M
Mohamad Saifudheen Thayyil

Least Common multiple in two numbers

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The lowest common multiple (LCM) is the smallest number that is a multiple of two numbers. For example, if we take the numbers 3 and 7, the LCM would be 21, as this is the smallest number that is divisible by both 3 and 7.

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M
Matthew Esan


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. 

T
Thilaxshi Suresh

In Maths it tends to mean ‘lowest common multiple’.

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LCM stands for "Lowest Common Multiple". When a question asks for the LCM, it wants to know what is the smallest number that appears in the times tables for two or more numbers. For example, the LCM of 4 and 5 would be 20 because 20 is the smallest number that appears in both the 4 times table AND the 5 times table.

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J
Joey Gemmell

Lowest common multiple! It is the lowest number that two different numbers can fit into exactly. You can find the LCM of two numbers by listing out their multiples and checking the lowest number that they both fit into.


You can also use a factor tree to find all of the two number's prime factors. You can then multiply all these prime factors together, but make sure to only include pairs of factors once!

K
Kiran

Lowest common multiple. So it is the smallest number that is easily (and evenly) divisible for all numbers required. What one number evenly divides all numbers in question.

E
Elisabeth Mountain

LCM stands for lowest common multiple. So if asked for the LCM of two numbers, you are trying to find a the smallest number that can be divided by both numbers with no remainder.

B
Bait-Toyin Ajani

Lowest common multiple. It's essentially the smallest number that is a multiple of 2 or more numbers. So for example, the smallest number that is a multiple of both 3 and 13 is 39.

N
Nisa

Stands for lowest common multiple which explained in the name is basically the lowest multiple that two different multiplication numbers have in common. This can be found using a common method with Venn diagrams.

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LCM stands for Least Common Multiple. The least common multiple of two numbers is the smallest number that is a multiple of both of them.

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Mary Neeson

This is the lowest common multiple

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