Is a an even integer?

Question

(1) ab is an even integer.
(2) b is an odd integer.

gmat6nplus1 · Accepted Answer

we don't know whether a is an integer in the first palce.

1) ab=even integer. assume a=√ 2 and b=√ 2; a is not an even integer. Assume a=2 and b=2; a is an even integer.

2) b is an odd integer. Not sufficient.

1+2) assume that a=2/3 and b=3 --> ab=even integer, but a is a proper fraction. Assume a=2 and b=3 --> ab=even integer and a is an even integer.

Answer E.

peachfuzz · Answer

I found it quickest to test numbers.

Statement 1: 
a = 1 b = 2 ab is even but a is not an even integer
a = 2 b = 1 ab is even, and a is an even integer
Insufficient

Statement 2: 
nothing is indicated about a.
Insufficient

Combined, a could be (2/3) and b could be 3. a is not an integer, and it is not even.
a could also be 2 and b could be 3, where in this case a is an even integer.
Insufficient

Answer: E

Bunuel · Answer

VERITAS PREP OFFICIAL SOLUTION

Correct Answer: E

Explanation:

(1) a and b could be 2 and 3, which would give us a YES answer to the question stem, or they could be 3 and 4, which gives us a NO. Accordingly, the statement is insufficient.

(2) This tells us nothing about a, and is therefore insufficient.

Together, a and b could be 2 and 3, which would give us a YES answer to the question, or they could be 2/3 and 3, which gives us an answer of NO. Because neither statement specifies that a must be an integer, we have to consider whether a fraction could be a potential value. Because it is possible to arrive at either answer the statements together are insufficient, and the correct answer is E.

mridupawandas · Answer

A is not sufficient as we don't know about b. Statement 2 is not sufficient clearly as it does not tell anything about a. Now if we combine both the statements we get the following situation ab=even integer and b is odd integer. at first glance it seems a should be even integer!! but what if I say lets suppose b=5 and for ab to be an even integer so lets say its =2 then a=2/5 hence a is not a even integer in this case again another situation b=5 and ab=10 then a =2 in this case a is an even integer.. so both statements not sufficient hence E. hope the detaled explanation helps..Kudos please!! :-)

stonecold · Answer

Taking B as 3 and A as 2/3 
and A as 2 and B as 3
we can say that E is the answer here
Smash E

stonecold · Answer

Superb Question this one=>
Here we need to see if A is even or not
NOTE => " A may or MAY not be an integer"
Statement1 => let B=0 => A can be even , odd or even or 83438949327493.343480 => not sufficient
Statement 2 => B is odd => No clue of A => not sufficient 
Now combining the statements => If A is an integer then it must be even but here the thing is if B=5 and A =4/5 then AB=4 hence A may be a fraction too => Not Suff

Smash that E.

NOTE => If A and B were given as integers then => C would be the choice as if AB=even and B is odd => A will be odd for A,B are integers.

exc4libur · Answer

(1) ab is an even integer.   insufic

ab=even*even;=odd*even

(2) b is an odd integer.   insufic

(1 and 2)   insufic

b=3: ab=6, a3=6, a=2
b=3: ab=2, a3=2, a=2/3

Ans (E)

bumpbot · Answer

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Is a an even integer?

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Is a an even integer?

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