Is the positive integer n odd?
(1) n= 2k+1, where K is positive integer
(2) 2n+1 is an odd integer
OA: B
I confused why the answer is B instead of D?
Is the positive integer n odd?
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What's the source of this question?ardz24 wrote:Is the positive integer n odd?
(1) n= 2k+1, where K is positive integer
(2) 2n+1 is an odd integer
OA: B
I confused why the answer is B instead of D?
I ask because the correct answer to this question is neither B nor D.
The correct answer is A
(1) If n= 2k+1 (where k is positive integer) then n is definitely odd. In fact, this is the actual definition of an odd integer.
(2) If n = 4, then 2n + 1 = (2)(4) + 1 = 9 (and odd number). In this case, n is EVEN
If n = 3, then 2n + 1 = (2)(3) + 1 = 7 (and odd number). In this case, n is ODD
So, statement 2 is NOT sufficient.
Answer: A
Cheers,
Brent