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LCM of 10,12,16
[#permalink]
01 Aug 2022, 18:52
01 Aug 2022, 18:52
Hi, this is a simple question. LCM of 10,12,16
GCF = 2
10 = 2 * 5
12 = 2 * 6
16 = 2 * 8
I keep getting LCM = 2*5*6*8 = 480. I know the right answer is 240. I have rewatched multiple videos but I think I am missing something simple.
GCF = 2
10 = 2 * 5
12 = 2 * 6
16 = 2 * 8
I keep getting LCM = 2*5*6*8 = 480. I know the right answer is 240. I have rewatched multiple videos but I think I am missing something simple.
LCM of 10,12,16
[#permalink]
01 Aug 2022, 23:43
01 Aug 2022, 23:43
Expert Reply
You need to take the highest factors among the numbers: common and NOT common, ONE time, only one.
\(12=2^2*3
\)
\(16=2^4\)
\(10=2*5\)
so the factors as per rule above are
\(2^4 * 3 * 5 =240\)
See here for a more and robust understanding of you basic skills
https://gre.myprepclub.com/forum/gre-math- ... 29378.html
\(12=2^2*3
\)
\(16=2^4\)
\(10=2*5\)
so the factors as per rule above are
\(2^4 * 3 * 5 =240\)
See here for a more and robust understanding of you basic skills
https://gre.myprepclub.com/forum/gre-math- ... 29378.html
Re: LCM of 10,12,16
[#permalink]
01 Aug 2022, 23:59
01 Aug 2022, 23:59
1
GreGuy22 wrote:
Hi, this is a simple question. LCM of 10,12,16
GCF = 2
10 = 2 * 5
12 = 2 * 6
16 = 2 * 8
I keep getting LCM = 2*5*6*8 = 480. I know the right answer is 240. I have rewatched multiple videos but I think I am missing something simple.
GCF = 2
10 = 2 * 5
12 = 2 * 6
16 = 2 * 8
I keep getting LCM = 2*5*6*8 = 480. I know the right answer is 240. I have rewatched multiple videos but I think I am missing something simple.
6 and 8 have a common factor, so you can't multiply 2*5*6*8 to find the LCM.
10 = 2 * 5
12 = 2 * 2 * 3
16 = 2 * 2 * 2 * 2
LCM = (2 * 5) * (2 * 3) * (2 * 2) = 10 * 6 * 4 = 240
We start with the factors of 10.
Then multiply with the additional factors of 12, so that the product is a multiple of 12. One 2 was already there, we added on the 3 and the second 2.
And finally multiply by the additional factors of 16. Two 2s were already there, so we added on two more 2s.
Is this clear?
Posted from my mobile device
