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What is the least common multiple of 6 and 9?

2 Answers

Answer:

#18#.

Explanation:

Go up in multiples of either #6# or #9#. so for #6#, there is:

#6#, #12#, #color(blue)(18)#, #24#...

for #9#, there is:

#9#, #color(blue)(18)#, #27#, #36#...

and find the earliest or lowest number that occurs in both, which is #18#.

Jul 26, 2017

Answer:

The least common multiple (LCM) of #6# and #9# is #18# and the explanation is down below!

Explanation:

I always take the first 5 multiples of each number and write them down. And if we don't our LCM in there, then I write down the next five multiples! So let's start, shall we?

(First 5) Multiples of #6#:
#6, 12, 18, 24, 30#

(First 5) Multiples of #9#:
#9, 18, 27, 36, 45#

Now, we have to see if there is any common number in the numbers. If we do, we have to make sure that there isn't any other number lower than that that #6# and #9# go into!

(First 5) Multiples of #6#:
#6, 12,##color(blue)(18)##, 24, 30#

(First 5) Multiples of #9#:
#9, ##color(blue)(18)##, 27, 36, 45#

There isn't any number before #18# that #6# and #9# both go into, so #18# is the LCM of #6# and #9#! Now we don't need to write down anymore multiples. :)

Source: My knowledge!

I hope that helps you!