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getzgetzu
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narsi
It is C.

1 Not suff - We donot know what is X. X can be 2525 in which case G will be 2531 or X can be other than 2525 in which case G will be 1.

2 Not suff - We donot know what is M and N.

Combine together. we have M = X + 6 and N = X + 7. 2 consecutive numbers and hence G is 1.


Why do u think B is not sufficient? I think B is! It shows that they are consecutive, hence relatively prime!
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shevy
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BG
From A) 2531 is a prime so M=q* 2531. Since 2531 is the GREATEST common factor, or G, then G-2531 so A SUF



How do you quickly determine if a number is prime?
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trick question. I agree with B
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Professor
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BG
From A) 2531 is a prime so M=q* 2531. Since 2531 is the GREATEST common factor, or G, then G-2531 so A SUF

From B) seems that M and N are consecutive integers and their GCF is 1 so B is SUFF

Tough Q :?


beautiful work. but how do you know that, in a, gcf is 2531? m could also be 2531. so gcf could be 1 or 2531.

agree with B.
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shevy
BG
From A) 2531 is a prime so M=q* 2531. Since 2531 is the GREATEST common factor, or G, then G-2531 so A SUF


How do you quickly determine if a number is prime?


Does anyone have any answer to this? I wouldn't be able to tell just by looking at the problem that 2531 is a prime number. Any shortcuts to calculate this?

Thanks!
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Definitely 'B'.

M=X+6; from 2) N=X+7.
M=N-1, so we have 1 as GCF.

Guys please remember me the rule when the digit is divided by 3, when by 4, by 6, by 7, by 8, by 9.
I forgot it. Just remember something like when the sum of the last 2 digits of any number is divided by 4 the number is divided by 4.

Thank you.



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