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If x is a positive integer, what is the units digit of 27x? Indicate a
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25 Aug 2021, 07:49
25 Aug 2021, 07:49
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Question Stats:
80% (00:41) correct
20% (01:46) wrong based on 5 sessions
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If x is a positive integer, what is the units digit of \(27^{x}\)?
Indicate all such digits.
(A) 1
(B) 2
(C) 3
(D) 7
(E) 9
Indicate all such digits.
(A) 1
(B) 2
(C) 3
(D) 7
(E) 9
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Official Answer
A,C,D,E
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Re: If x is a positive integer, what is the units digit of 27x? Indicate a
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25 Aug 2021, 08:18
25 Aug 2021, 08:18
Carcass wrote:
If x is a positive integer, what is the units digit of \(27^{x}\)?
Indicate all such digits.
(A) 1
(B) 2
(C) 3
(D) 7
(E) 9
Indicate all such digits.
(A) 1
(B) 2
(C) 3
(D) 7
(E) 9
Cylicity of 7 is 4 i.e. the units digit repeats every 4 terms
\(7^1\) = 7
\(7^2\) = 49
\(7^3\) = 343
\(7^4\) = 2,401
\(7^5\) = 16,807
Hence, option A, C, D and E
gmatclubot
Re: If x is a positive integer, what is the units digit of 27x? Indicate a [#permalink]
25 Aug 2021, 08:18
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