BTGmoderatorDC wrote: ↑Wed Apr 20, 2022 2:37 am
Is the product of a certain pair of integers even?
(1) The sum of the integers is odd.
(2) One of the integers is even and the other is odd.
OA
D
Source: GMAT Prep
Some important rules:
1. ODD +/- ODD = EVEN
2. ODD +/- EVEN = ODD
3. EVEN +/- EVEN = EVEN
4. (ODD)(ODD) = ODD
5. (ODD)(EVEN) = EVEN
6. (EVEN)(EVEN) = EVEN
Target question: Is the product of a certain pair of integer even?
Statement 1: The sum of the integers is odd
So, if the sum is odd, we know that one integer is ODD, and one integer is EVEN (
rule #2)
If one integer is ODD, and one integer is EVEN, then
their product must be even (
rule #5).
Since we can answer the
target question with certainty, statement 1 is SUFFICIENT
Statement 2: One of the integer is even and odd
If one integer is ODD, and one integer is EVEN, then
their product must be even (
rule #5).
Since we can answer the
target question with certainty, statement 2 is SUFFICIENT
Answer = D
Cheers,
Brent
