Reposting these 3 problem on LCM and GCD coz that post had no replies.
Can the experts pls help me here.
G, M, and N are integers, M=X+6; G is the greatest common factor of M and N. G=?
1) N=2531
2) N=X+7
X and Y are positive integers. What is the maximum common divisor of X and Y?
a) X=Y+1
b) X is a multiple of 2
What is the greatest common factor of positive integers x and y?
1) The greatest common factor of and is 5
2) x and y are even
3 more problems on LCM GCD
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For 2nd,
What is the maximum common divisor of X and Y?
a) X=Y+1 -- This means that X and Y are consecutive integers. Then, the GCD is always 1 (Which is the maximum GCD)
Sufficient.
b) We don't know what Y is. Insufficient.
Answer: A
Can you check the 1st statement of 3rd question? It is not clear
What is the maximum common divisor of X and Y?
a) X=Y+1 -- This means that X and Y are consecutive integers. Then, the GCD is always 1 (Which is the maximum GCD)
Sufficient.
b) We don't know what Y is. Insufficient.
Answer: A
Can you check the 1st statement of 3rd question? It is not clear
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1) M could still have infinite values, and no relationship between M and N, so insufficient.vittalgmat wrote:Reposting these 3 problem on LCM and GCD coz that post had no replies.
Can the experts pls help me here.
G, M, and N are integers, M=X+6; G is the greatest common factor of M and N. G=?
1) N=2531
2) N=X+7
2) If M = X + 6 and N = X + 7, then M and N are consecutive integers. Therefore, their GCF is 1... sufficient!
2 is sufficient, 1 isn't: choose B.
Statement (1) is missing info (which is probably why it got ignored the first time around).What is the greatest common factor of positive integers x and y?
1) The greatest common factor of and is 5
2) x and y are even
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Thanks everyone for the replies.
I could not find the rest of the problem either.. we will probably have to leave it as it is.
I could not find the rest of the problem either.. we will probably have to leave it as it is.
2) If M = X + 6 and N = X + 7, then M and N are consecutive integers. Therefore, their GCF is 1... sufficient!
2 is sufficient, 1 isn't: choose B.
What if they are 0 and 1. There is no mention in the question that the integers are positive.
In that case how will 1 be the GCF.
So it should be C
2 is sufficient, 1 isn't: choose B.
What if they are 0 and 1. There is no mention in the question that the integers are positive.
In that case how will 1 be the GCF.
So it should be C
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You're correct!pink_08 wrote:2) If M = X + 6 and N = X + 7, then M and N are consecutive integers. Therefore, their GCF is 1... sufficient!
2 is sufficient, 1 isn't: choose B.
What if they are 0 and 1. There is no mention in the question that the integers are positive.
In that case how will 1 be the GCF.
So it should be C
I'm guessing the author of the question meant the answer to be B and just forgot about 0 issues.
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Actually, I retract my previous statements.Stuart Kovinsky wrote:You're correct!pink_08 wrote:2) If M = X + 6 and N = X + 7, then M and N are consecutive integers. Therefore, their GCF is 1... sufficient!
2 is sufficient, 1 isn't: choose B.
What if they are 0 and 1. There is no mention in the question that the integers are positive.
In that case how will 1 be the GCF.
So it should be C
I'm guessing the author of the question meant the answer to be B and just forgot about 0 issues.
0 is a multiple of all numbers except 0 (since 0/x = 0 for all values of x except 0).
So, even if our values are negative (which we usually don't think about when dealing with concepts such as GCF and LCM, which is why I think not stating we were dealing with positives was an oversight), the GCF will still be 1.
For example, if our numbers are -14 and -15,
-14 = 1*-14
-15 = 1*-15
so 1 would still be the GCF.
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