If n and t are positive integers, is n a factor of t?
(1) n = 3^n-z
(2) t = 3^n
Can anyone pls help?
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moneyman
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If n and t are positive integers, is n a factor of t?
(1) n = 3^n-z
(2) t = 3^n
Is the answer B??
(1) is insufficient because it does not say anything about t.
(2) is sufficient because n will be a factor of t if t/n is an integer..Statement 2 says that t=3^n ..Substitute values and you will find that all the values satisfy the condition..
(1) n = 3^n-z
(2) t = 3^n
Is the answer B??
(1) is insufficient because it does not say anything about t.
(2) is sufficient because n will be a factor of t if t/n is an integer..Statement 2 says that t=3^n ..Substitute values and you will find that all the values satisfy the condition..
Maxx
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givemeanid
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(1) is insufficient. We don't know anything about t or z.
(2) is insufficient. t = 3^n. For n = 3, t = 27. n is a factor of t. For n = 5, t = 243. n is not a factor of t.
It is (E)
(2) is insufficient. t = 3^n. For n = 3, t = 27. n is a factor of t. For n = 5, t = 243. n is not a factor of t.
It is (E)
Assuming 'z' is a mistyped characted, and its really 't', can you please explain how you arrived at [C], PennMI?PennMI wrote:Is the question mistyped? If the "z" is supposed to be a "t", then I see how the answer is C...but, if not, then answer should be E.
If n and t are positive integers, is n a factor of t?
(1) n = 3^n-z
(2) t = 3^n
If z is supposed to be t, here was my logic for "C":
(1) insufficient. No info about t.
(2) insufficient. if n = 2; t=9...answer is "no". if n=1; t=3...answer is "yes".
Rephrasing the question, it is asking if (t/n) is an integer. Taken together, if you look at t/n, you get (3^n)/(3^n-t). Due to same base, you can subtract exponents so, t/n = n-(n-t) = n-n+t = t. So, t/n = t. Because "t" is an integer, I would say "C".
(1) n = 3^n-z
(2) t = 3^n
If z is supposed to be t, here was my logic for "C":
(1) insufficient. No info about t.
(2) insufficient. if n = 2; t=9...answer is "no". if n=1; t=3...answer is "yes".
Rephrasing the question, it is asking if (t/n) is an integer. Taken together, if you look at t/n, you get (3^n)/(3^n-t). Due to same base, you can subtract exponents so, t/n = n-(n-t) = n-n+t = t. So, t/n = t. Because "t" is an integer, I would say "C".
I just re-read my post and noticed I wrote "due to" in my response. Just pointing out that that's wrong since you can't use "due to" in place of "because"; you can only use "due to" to replace "caused by". Just thought I'd throw in that little SC tidbit since my verbal skills are awful. Anyways, I think I'm starting to catch on 
