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Sub 505 (Easy)|   Exponents|      
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Bunuel
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If 8^13 = 2^z , then z = 21 May 2017, 12:44
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E
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!

Difficulty:

5% (low)

Question Stats:

86% (00:28) correct 14% (00:28) wrong based on 63 sessions

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If \(8^{13} = 2^z\) , then z =

(A) 10
(B) 13
(C) 19
(D) 26
(E) 39
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E
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nishantt7
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If 8^13 = 2^z , then z = 21 May 2017, 12:48
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Bunuel
If \(8^{13} = 2^z\) , then z =

(A) 10
(B) 13
(C) 19
(D) 26
(E) 39
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Answer is E.

2^3*13=2^Z
Z=39
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If 8^13 = 2^z , then z = 21 May 2017, 18:38
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Bunuel
If \(8^{13} = 2^z\) , then z =

(A) 10
(B) 13
(C) 19
(D) 26
(E) 39
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\(8^{13} = 2^z\)
8 = \(2^3\)
\((2^3)^{13} = 2^z\)
\(2^{39} = 2^z\)
z = 39
Answer E...

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If 8^13 = 2^z , then z = 22 May 2017, 09:21
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Bunuel
If \(8^{13} = 2^z\) , then z =

(A) 10
(B) 13
(C) 19
(D) 26
(E) 39
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\(2^{26} = 2^z\)

So, \(z = 26\)

Thus, answer will be (D) 26
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If 8^13 = 2^z , then z = 22 May 2017, 10:41
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Abhishek009
Bunuel
If \(8^{13} = 2^z\) , then z =

(A) 10
(B) 13
(C) 19
(D) 26
(E) 39

\(2^{26} = 2^z\)

So, \(z = 26\)

Thus, answer will be (D) 26
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2^2 does not equal 8

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JS1290
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If 8^13 = 2^z , then z = 22 May 2017, 10:48
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Abhishek009
Bunuel
If \(8^{13} = 2^z\) , then z =

(A) 10
(B) 13
(C) 19
(D) 26
(E) 39

\(2^{26} = 2^z\)

So, \(z = 26\)

Thus, answer will be (D) 26
Show more

Hi,

I am a bit confused here. Shouldn't the answer be E instead? 8=2^3 which means 3*13=39. I am not quite sure how you got 26 as your answer. Could you please explain?
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matthewsmith_89
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If 8^13 = 2^z , then z = 22 May 2017, 13:19
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csaluja
Abhishek009
Bunuel
If \(8^{13} = 2^z\) , then z =

(A) 10
(B) 13
(C) 19
(D) 26
(E) 39

\(2^{26} = 2^z\)

So, \(z = 26\)

Thus, answer will be (D) 26

Hi,

I am a bit confused here. Shouldn't the answer be E instead? 8=2^3 which means 3*13=39. I am not quite sure how you got 26 as your answer. Could you please explain?
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The answer is E. Not D Abhishek009's solution is incorrect.
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If 8^13 = 2^z , then z = 17 Apr 2019, 22:40
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we are told that
\(8^{13}=2^{z}\)
writing 8 as 2^{3}
\(({2^{3}})^{13}=2^{z}\)

\(2^{39}=2^{z}\)

we can equate bases if the bases are same, so
z= 39
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