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least common multiple of two positive integers x and y

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by November Rain » Thu May 13, 2010 10:01 am
Hi,

One of the properties of the LCM and GCF is that the LCM * GCF = XY

Assuming that the GCF (Greatest Common Factor) is 2, then we would have LCM * 2 = XY, or LCM = XY/2
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by GauravMalhotra » Thu May 13, 2010 10:10 am
M811 wrote:If x > y > 1, which of the following could be the least common multiple of two positive integers x and y ?
(A) x + 1
(B) y - 1
(C) x - y
(D) xy - 1
(E) xy/2

[spoiler]ANS :E[/spoiler]
doesn't look to be the correct question (or something is missing)

x = 3 and y = 2... the answer doesn't satisfy.... similarly.. x=8 and y=3....
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by November Rain » Thu May 13, 2010 10:17 am
It says "which of the following could be the least common multiple", not that it must be.

Try X=6 and Y = 4
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by debmalya_dutta » Thu May 13, 2010 11:56 am
by value substitution in x and y
y= 2 and x = 4
lowest common multiple = 4
hence xy/2 is the right answer
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by cager » Thu May 13, 2010 12:17 pm
November Rain wrote:It says "which of the following could be the least common multiple", not that it must be.

Try X=6 and Y = 4
tricky
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