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What is the difference between the sixth and the fifth terms
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20 Dec 2012, 09:02
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84% (01:25) correct 16% (01:30) wrong based on 1560 sessions
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What is the difference between the sixth and the fifth terms of the sequence 2, 4, 7, ... whose nth term is n + 2^(n  1)? (A) 2 (B) 3 (C) 6 (D) 16 (E) 17
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Re: What is the difference between the sixth and the fifth terms
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20 Dec 2012, 09:04
Walkabout wrote: What is the difference between the sixth and the fifth terms of the sequence 2, 4, 7, ... whose nth term is n + 2^(n  1)?
(A) 2 (B) 3 (C) 6 (D) 16 (E) 17 Given that \(a_n=n+2^{n1}\), thus: \(a_6=6+2^{61}=38\); \(a_5=5+2^{51}=21\); The difference is 3821=17. Answer: E.
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Re: What is the difference between the sixth and the fifth terms
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29 Jun 2017, 19:28
Notice that 2 raised to any positive number will aways be even.
Hence the sixth term will be even+even = even The fifth term will be odd+even = odd
The only two answers that are odd are B and E. I would say that looking at the sequence we can say that the gap is expanding, hence answer is E



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Re: What is the difference between the sixth and the fifth terms
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25 Nov 2014, 14:02
Bunuel wrote: Walkabout wrote: What is the difference between the sixth and the fifth terms of the sequence 2, 4, 7, ... whose nth term is n + 2^(n  1)?
(A) 2 (B) 3 (C) 6 (D) 16 (E) 17 Given that \(a_n=n+2^{n1}\), thus: \(a_6=6+2^{61}=38\); \(a_5=5+2^{51}=21\); The difference is 3821=17. Answer: E. Just one question, why do they mention 2, 4, 7. Is that to throw a testtaker off?
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Re: What is the difference between the sixth and the fifth terms
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26 Nov 2014, 05:10
Bigred2008 wrote: Bunuel wrote: Walkabout wrote: What is the difference between the sixth and the fifth terms of the sequence 2, 4, 7, ... whose nth term is n + 2^(n  1)?
(A) 2 (B) 3 (C) 6 (D) 16 (E) 17 Given that \(a_n=n+2^{n1}\), thus: \(a_6=6+2^{61}=38\); \(a_5=5+2^{51}=21\); The difference is 3821=17. Answer: E. Just one question, why do they mention 2, 4, 7. Is that to throw a testtaker off? 2, 4, and 7, are the first, second and the third terms of the sequence whose nth term is n + 2^(n  1). For n = 1, n + 2^(n  1) = 1 + 2^0 = 2, for n = 2, n + 2^(n  1) = 2 + 2^1 = 4, and for n = 3, n + 2^(n  1) = 3 + 2^2 = 7. So, those numbers are given simply as an example.
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Re: What is the difference between the sixth and the fifth terms
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13 Jul 2016, 07:30
Walkabout wrote: What is the difference between the sixth and the fifth terms of the sequence 2, 4, 7, ... whose nth term is n + 2^(n  1)?
(A) 2 (B) 3 (C) 6 (D) 16 (E) 17 For the sixth term, we need to substitute 6 for n, and for the fifth term, we need to substitute 5 for n. Then we'll find the difference between the two terms. Let’s first plug 6 in for n. 6 + 2^(61) 6 + 2^5 6 + 32 = 38 Next let’s plug 5 in for n. 5 + 2^(51) 5 + 2^4 5 + 16 = 21 Thus, the difference between the 6th and 5th term of the sequence is 38 – 21 = 17. Answer is E.
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Re: What is the difference between the sixth and the fifth terms
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31 Jan 2017, 17:37
Plug in 6 and 5 for the sixth and fifth sequence respectively.....
Sixth sequence = 6 + 2^(61) = 38
Fifth sequence = 5 + 2^(51) = 21
3821 = 17



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Re: What is the difference between the sixth and the fifth terms
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22 Oct 2019, 07:27
What is the difference between the sixth and the fifth terms of the sequence 2, 4, 7, ... whose nth term is n + 2^(n  1)?
(A) 2 (B) 3 (C) 6 (D) 16 (E) 17> correct
Analysis: t6t5 = 6 + 2^5  5 2^4=1+2^4=17



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Re: What is the difference between the sixth and the fifth terms
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26 Nov 2019, 09:23
n6 = 6+2^5 n5 = 5+2^4
n6n5= 6+2^5(5+2^4) =1+2^52^4 =1+2^4(21) =1+16(1) =17




Re: What is the difference between the sixth and the fifth terms
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26 Nov 2019, 09:23






