What is the value of N?

Question

(1) (N + 5)^3> 0
(2) (N - 5)^2≤ 0

Bunuel · Answer

What is the value of N?

In order the answer to be B it should be as follows:

(1) (N + 5)^3> 0 --> n+5>0 --> n>-5, not sufficient to determine single numerical value of n.

(2) (N - 5)^2≤ 0 --> as square of a number is always non-negative (zero or positive), then (n-5)^2 can not be less than zero thus it must equal to zero: n-5=0 --> n=5. Sufficient.

Answer: B.

MichelleSavina please check the questions for typos when posting.

MichelleSavina · Answer

edited it.... next time will check it before i post it

MathRevolution · Answer

Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution.

Since we have 1 variable and 0 equations, D is most likely to be the answer. So, we should consider each of condition one by one first.

Condition 1):
N = 0, N = 1
Since we have many solutions, the condition 1) is not sufficient.

Condition 2)
We have the property (N-5)^2 ≥ 0 and (N-5)^2 ≤ 0 fromt the condition 2).
Since 0≤(N-5)^2 ≤ 0, we have (N-5)^2 = 0 or N = 5.
The condition 2) only is not sufficient.

Therefore, B is the answer.

If the original condition includes “1 variable”, or “2 variables and 1 equation”, or “3 variables and 2 equations” etc., one more equation is required to answer the question. If each of conditions 1) and 2) provide an additional equation, there is a 59% chance that D is the answer, a 38% chance that A or B is the answer, and a 3% chance that the answer is C or E. Thus, answer D (conditions 1) and 2), when applied separately, are sufficient to answer the question) is most likely, but there may be cases where the answer is A,B,C or E.

bumpbot · Answer

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What is the value of N?

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GMAT Data Sufficiency (DS) Questions

What is the value of N?

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