If n is an integer, then is n even?
1) n(n+2)=even
2) n(n+3)=even
The OA is the option A.
Why is not sufficient the statement (2)? Experts, can you help me? Please.
is an integer n even?
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Statement 1:VJesus12 wrote:If n is an integer, then is n even?
1) n(n+2)=even
2) n(n+3)=even
Case 1: n=1, with the result that n(n+2) = 1*3 = 3
Since the value in red is not even, Case 1 is not viable.
Case 2: n=3, with the result that n(n+2) = 3*5 = 15
Since the value in red is not even, Case 2 is not viable.
Case 3: n=5, with the result that n(n+2) = 5*7 = 35
Since the value in red is not even, Case 3 is not viable.
The cases above illustrate that NO ODD VALUE will satisfy Statement 1.
Thus, n must be EVEN, and the answer to the question stem is YES.
SUFFICIENT.
Statement 2:
Case 1: n=1, with the result that n(n+3) = 1*4 = 4
In this case, n is ODD, so the answer to the question stem is NO.
Case 1: n=2, with the result that n(n+3) = 2*5 = 10
In this case, n is EVEN, so the answer to the question stem is YES.
Since the answer is NO in Case 1 but YES in Case 2, INSUFFICIENT.
The correct answer is A.
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I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
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