Official Guide Explanation:
Data Sufficiency #23




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Solution and Metadata

Question: 23
Page: 274
Difficulty: 4 (Moderately Easy)
Category 1: Word Problems > Profit >

Explanation: Since the question includes the caveat "though not proportionally," you can't set up a ratio to find the profit per unit. Statement (1) is not sufficient: we have no idea how much additional profit would come from the next 180,000 units, or if it would exceed $2 million.

Statement (2) is sufficient: 350,000 units already results in more profit than $4 million. If the profit increases with each additional unit sold, then the profit on 380,000 units must be more than $5 million, so, of course, more than $4 million as well. Choice (B) is correct.

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