If n = (16/81)^(1/2), what is the value of n^(1/2)?
(A) 1/9
(B) 1/4
(C) 4/9
(D) 2/3
(E) 9/2
D
OG Square root of 16/81
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We have n = (16/81)^(1/2) = (4^2/9^2)^(1/2) = 4/9AbeNeedsAnswers wrote:If n = (16/81)^(1/2), what is the value of n^(1/2)?
(A) 1/9
(B) 1/4
(C) 4/9
(D) 2/3
(E) 9/2
D
n^(1/2) = (4/9)^(1/2)
n^(1/2) = (2^2/3^2)^(1/2) = [spoiler]2/3[/spoiler]
The correct answer: D
Hope this helps!
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Note also that when you take the root of a fraction between 0 and 1, the value of the fraction increases and moves closer to 1.
If n = 4/9, then √ (4/9) must be between 4/9 and 1. The only value in that range is 2/3. (Not that it's terribly difficult to find √ 4 and √ 9, but this property is helpful if you're given, say, √ .6.)
If n = 4/9, then √ (4/9) must be between 4/9 and 1. The only value in that range is 2/3. (Not that it's terribly difficult to find √ 4 and √ 9, but this property is helpful if you're given, say, √ .6.)
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Hi Jabs80,Jabs80 wrote:4/9AbeNeedsAnswers wrote:If n = (16/81)^(1/2), what is the value of n^(1/2)?
(A) 1/9
(B) 1/4
(C) 4/9
(D) 2/3
(E) 9/2
D
It looks like you caught your error, which is good. As you continue to study, you have to be mindful that the 4 wrong answers to any GMAT question are rarely 'random' - and some of those answers can be answers to DIFFERENT questions (so you have to be careful and make sure that you're answering the question that is ASKED). Here, while Answer C is the value of N, that is not what this question is asking for.
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We can simplify the given equation:AbeNeedsAnswers wrote:If n = (16/81)^(1/2), what is the value of n^(1/2)?
(A) 1/9
(B) 1/4
(C) 4/9
(D) 2/3
(E) 9/2
D
n = (16/81)^(1/2)
n = 4/9
Thus, n^(1/2) = 4/9^(1/2) = 2/3.
Answer: D
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The half power is the same as the square root, so for legibility's sake let's write:
n = √16/81
n = 4/9
From here, √n = √4/9 = 2/3.
n = √16/81
n = 4/9
From here, √n = √4/9 = 2/3.
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Hi All,
When taking the square root of a fraction, you must take the square root of the numerator and the square root of the denominator.
Here, the square root of 16/81 = 4/9
We're then asked to calculate the square root of 4/9.... and that would be 2/3
Final Answer: D
GMAT assassins aren't born, they're made,
Rich
When taking the square root of a fraction, you must take the square root of the numerator and the square root of the denominator.
Here, the square root of 16/81 = 4/9
We're then asked to calculate the square root of 4/9.... and that would be 2/3
Final Answer: D
GMAT assassins aren't born, they're made,
Rich