Extra Divisibility & Primes

[MarthaM266]

Given DS:

Is N divisible by 7?

1 - N = x-y, where x and y are integers
2 - x is divisible by 7, and y is not divisible by 7

If y is zero wouldn't it be impossible and therefore E?

[tim]

Statement 2 says that y is not divisible by 7, so you cannot choose an example a number that is divisible by 7. 0 is divisible by 7, so it is not a valid example.

BTW if you're not sure why 0 is divisible by 7, ask yourself what it means to be divisible by 7. You may want to review this definition further if you are not applying it correctly.

[RonPurewal]

more importantly, the official gmat problems are written so as to ensure that these kinds of 'fringe' cases (= where the issue is not conceptual understanding at all, but rather just nit-picking the niceties of a definition) do not matter.

i wrote about this here:
https://www.manhattanprep.com/gmat/foru ... ml#p116154