OG Square root of 16/81

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

We have n = (16/81)^(1/2) = (4^2/9^2)^(1/2) = 4/9

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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Jabs80 wrote:

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

4/9

Hi Jabs80,

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.

GMAT assassins aren't born, they're made,
Rich

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

We can simplify the given equation:

n = (16/81)^(1/2)

n = 4/9

Thus, n^(1/2) = 4/9^(1/2) = 2/3.

Answer: D

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