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itslateagain_7
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Hi guys,
I've searched all over the web and was sure I could find the answer to this question but it eludes me. It's from the Kaplan math workbook, Data Sufficiency Test 1, question 24, p320.
The answer in the book is completely off, as in taken from the wrong question. This error is alluded to by Todd Scheceter in his review on Amazon (https://www.amazon.com/Kaplan-GMAT-Math- ... Descending) yet nobody has responded to his request for the answer.
To that end, I present the question in full here:
S is a set of positive integers such that if integer x is a member of S, then both x squared and x cubed are also in S. If the only member of S that is neither the square nor the cube of another member of S is called the source integer, is 8 in S?
(1) 4 is in S and is not the source integer.
(2) 64 is in S and is not the source integer.
--
Anybody care to help me by providing the solution?
--
For me, I'm having trouble figuring out what exactly the relationship between 4 and 64 are with S. I would imagine if 4 is not a source integer, then it is the square or cube of another set member; ex) the square of 2.
If 2 is in S, then its cube, 8, will be in S. So statement (1) is sufficient.
If 64 is in S, and isn't the source integer, then it is the square of another number, that being 8. 8 is in S, statement (2) is sufficient as well, and so the answer to the question is thus: "Either statement by itself is sufficient."
Does that correspond to others' thoughts?
Thank you,
Mark
I've searched all over the web and was sure I could find the answer to this question but it eludes me. It's from the Kaplan math workbook, Data Sufficiency Test 1, question 24, p320.
The answer in the book is completely off, as in taken from the wrong question. This error is alluded to by Todd Scheceter in his review on Amazon (https://www.amazon.com/Kaplan-GMAT-Math- ... Descending) yet nobody has responded to his request for the answer.
To that end, I present the question in full here:
S is a set of positive integers such that if integer x is a member of S, then both x squared and x cubed are also in S. If the only member of S that is neither the square nor the cube of another member of S is called the source integer, is 8 in S?
(1) 4 is in S and is not the source integer.
(2) 64 is in S and is not the source integer.
--
Anybody care to help me by providing the solution?
--
For me, I'm having trouble figuring out what exactly the relationship between 4 and 64 are with S. I would imagine if 4 is not a source integer, then it is the square or cube of another set member; ex) the square of 2.
If 2 is in S, then its cube, 8, will be in S. So statement (1) is sufficient.
If 64 is in S, and isn't the source integer, then it is the square of another number, that being 8. 8 is in S, statement (2) is sufficient as well, and so the answer to the question is thus: "Either statement by itself is sufficient."
Does that correspond to others' thoughts?
Thank you,
Mark
