Official Guide Explanation:
Data Sufficiency #50




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Solution and Metadata

Question: 50
Page: 156
Difficulty: 5 (Moderate)
Category 1: Algebra > Linear Equations-Two Unk >
Category 2: Arithmetic > Percents > other

Explanation: Given the total price of the stock, to determine the price per share, you need the number of shares. In other words, p = ((12,000)/(n)). Statement (1) is sufficient: it provides another equation with the same two variables, p + 1 = ((12,000 + 300)/(n)). Given those two equations with the same two variables, you could solve for p.

Statement (2) is also sufficient; again, you can set up another equation with p and n: p - 2 = ((12,000 - (0.05)12,000)/(n)). With two linear equations and two variables, you can solve for p. Choice (D) is correct.

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