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All You Need to Know about LCM & GCF 749 Views
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Description:
This video covers Least Common Multiple and Greatest Common Factor. What are they? How do you find them? How does factorization play in?
Transcript
- 00:00
Thank you We sneak l c m and g c
- 00:05
f allah shmoop What are these Mysterious acronyms Top secret
- 00:10
government organizations A new form of text speak or perhaps
- 00:14
a misplaced scrabble tiles Actually they're abbreviations for mathematical concepts
- 00:20
Well l c m is an acronym for least common
Full Transcript
- 00:24
Multiple let's Take a look at that one first Not
- 00:27
so close Let's Back it up a bit boys Keep
- 00:29
he beep There there There we go Uh first we
- 00:33
need to talk about what a multiple is save Got
- 00:35
the number six multiple is any number that can result
- 00:38
from multiplying are given number by any other number For
- 00:41
example you gonna multiply six by one to get six
- 00:44
by to get twelve Buy three to get eighteen by
- 00:47
four to get twenty four and so on Six twelve
- 00:50
eighteen and twenty four are all multiples of six If
- 00:53
you want to find the multiples of eight you can
- 00:55
multiply eight by one to get ate by two to
- 00:58
get sixteen and buy three to get twenty four We
- 01:01
could keep going but we can see you're in a
- 01:03
hurry if you want to find the least common multiple
- 01:05
Of six and a you need to find the smallest
- 01:08
number that shares both numbers as factors as you can
- 01:11
see it's unfortunately not as easy as merely multiplying the
- 01:14
numbers together G c f or greatest common factor is
- 01:18
basically the reverse When looking for a g c f
- 01:21
you need to find the largest number that will divide
- 01:23
evenly into two other Numbers take the numbers 36 and
- 01:27
forty eight okay wiseguy put him back suppose you're given
- 01:30
the number of thirty six and forty eight what factors
- 01:33
that they have in common Well both Numbers are even
- 01:36
so 2 works three is also a factor as our
- 01:39
foreign six but the greatest common factor the granddaddy of
- 01:42
them all is twelve shmoop a good way to find
- 01:47
the gcs is to first use prime factory ization thirty
- 01:51
six breaks down into two times two times three times
- 01:54
three forty eight breaks down into two times two times
- 01:58
two times two times three the Numbers that the 2
- 02:02
have in common are the two twos and a three
- 02:05
multiply those out and voila twelve practice finding l c
- 02:10
m's and gcs on your own and it will pay
- 02:12
Dividends Just don't let the catch you Those guys are 00:02:15.828 --> [endTime] not to be trifled with
Up Next
It's impressive that these expressions are able to stay so rational even when they're having operations performed on them.
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