Official Guide Explanation:
Data Sufficiency #38




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Solution and Metadata

Question: 38
Page: 155
Difficulty: 5 (Moderate)
Category 1: Word Problems > Work Problems > 2 inputs
Category 2: Word Problems > Rate Problems > Combined Rate

Explanation: To find the amount of time it would take for both machines to produce the lot of cans, you need the rate at which machine Y runs. Statement (1) is sufficient: we know the rate at which X runs, and if they are equal, we also know Y's rate. Statement (2) is also sufficient: if it takes X twice as long as it takes X and Y combined to produce the lot, that means it takes 1 hour for X and Y combined to produce the lot, which is all the information needed to determine the answer. Choice (D) is correct.

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