Bunuel wrote:

If n + k = m, what is the value of k ?

(1) n = 10

(2) m + 10 = n

We are given that n + k = m, and we need to determine the value of k. Since we know that n + k = m, we know that k = m – n. Thus, if we determine a value for m – n, we will know the value of k.

Statement One Alone:n = 10

Although we know that n = 10, without knowing the value of m, we cannot determine the value of k. Statement one alone is not sufficient. We can eliminate answer choices A and D.

Statement Two Alone:m + 10 = n

Manipulating statement two we get:

m + 10 = n

m – n = -10

Since we know that m – n = -10, we know that k = -10. Statement two alone is sufficient.

The answer is B.

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Scott Woodbury-Stewart

Founder and CEO

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