AAPL wrote:e-GMAT
$$\text{If } a, b, c, d \text{ are 4 non-negative integers. Is } (a+c) \text{ even?}$$
$$1.\ a^2+b^2+c^2\ \text{ is even.}$$
$$2.\ b^2+c^2+d^2\ \text{ is even.}$$
OA E
Given: a, b, c, d are 4 non-negative integers.
We have to determine whether (a + c) is even.
Let's take each statement one by one.
(1) a^2 + b^2 + c^2 is even.
Case 1: Say a = 0; b = c = 1, then we have a^2 + b^2 + c^2 = 0^2 + 1^2 + 1^2 = 2, an even number. However, a + c = 0 + 1 = 1, an odd number; the answer is no.
Case 2: Say b = 0; a = c = 1, then we have a^2 + b^2 + c^2 = 1^2 + 0^2 + 1^2 = 2, an even number. We see that a + c = 1 + 1 = 2, an even number; the answer is yes.
No unique answer. Insufficient.
(2) b^2 + c^2 + d^2 is even.
No information about a. Insufficient.
(1) and (2) together
Even after combining the two statements, both the cases discussed in Statement 1 are applicable. Insufficient.
The correct answer:
E
Hope this helps!
-Jay
_________________
Manhattan Review GMAT Prep
Locations:
GMAT Classes Tampa |
GMAT Tutoring DC |
GRE Prep San Francisco |
TOEFL Prep Classes Chicago | and many more...
Schedule your free consultation with an experienced GMAT Prep Advisor!
Click here.
