is fg + 2 prime?
(1) f is odd.
It give a huge variety of no. its uncertain...Note in Yes/No ques if its yes then sufficient if its no then also sufficient but if uncertain then insufficient..
Insufficient.
(2) g is even.
again gives a wide variety . Insufficient.
Now if we conclude 1 and 2
fg + 2
1+2+2 =5 Yes
5 +10+2=17 yes
21+20+2 =yes
11+2+2= 15 No
Two answers is definitely Insufficient..
IMO E
Princeton_ I think its answer is wrong!!!
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- prateek_guy2004
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Don't look for the incorrect things that you have done rather look for remedies....
https://www.beatthegmat.com/motivation-t90253.html
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thestartupguy
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IMO E
Statement 1 is easy and not-sufficient
Statement 2: Consider 0 (even integer) and hence not-sufficient
So E
Statement 1 is easy and not-sufficient
Statement 2: Consider 0 (even integer) and hence not-sufficient
So E
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Hmm...where this one probably gets tricky in terms of solution is that:
Statement 1 is not sufficient. f could be 5 and g 1, and 5 + 2 is prime; or f could be 7 and g 1, and 7 + 2 is not.
Statement 2, as it's written, is NOT sufficient, but only because g could still be 0, and 0 + 2 is prime (2). For all other values of g (assuming that f is not also 0), fg + 2 is not prime.
So, as written, the correct answer should be E. But if they tweaked it to "f and g are POSITIVE integers" it would be B.
Statement 1 is not sufficient. f could be 5 and g 1, and 5 + 2 is prime; or f could be 7 and g 1, and 7 + 2 is not.
Statement 2, as it's written, is NOT sufficient, but only because g could still be 0, and 0 + 2 is prime (2). For all other values of g (assuming that f is not also 0), fg + 2 is not prime.
So, as written, the correct answer should be E. But if they tweaked it to "f and g are POSITIVE integers" it would be B.
Brian Galvin
GMAT Instructor
Chief Academic Officer
Veritas Prep
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GMAT Instructor
Chief Academic Officer
Veritas Prep
Looking for GMAT practice questions? Try out the Veritas Prep Question Bank. Learn More.












