Is z an integer?
(1) 2z is an even number.
(2) 4z is an even number.
[spoiler]OA=A[/spoiler]
Why is sufficient the first statement but the second one isn't? I think both statements say almost the same. I need help here. Thanks in advance.
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Is z an integer?
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Statement 1:Gmat_mission wrote:Is z an integer?
(1) 2z is an even number.
(2) 4z is an even number.
Options for 2z:
2z = 2, 4, 6, 8, 10, 12...
Dividing every value above by 2, we get the following options for z:
z = 1, 2, 3, 4, 5, 6...
In every case, z is an integer.
Thus, the answer to the question stem is YES.
SUFFICIENT.
Statement 2:
Options for 4z:
4z = 2, 4, 6, 8, 10, 12...
Dividing every value above by 4, we get the following options for z:
z = 1/2, 1, 3/2, 2, 5/2, 3...
If z = 1/2, then the answer to the questions stem is NO.
If z=1, then the answer to the question stem is YES.
Since the answer is NO in the first case but YES in the second case, 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.
For more information, please email me (Mitch Hunt) at [email protected].
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