Official Guide Explanation:
Data Sufficiency #119




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Solution and Metadata

Question: 119
Page: 283
Difficulty: 4 (Moderately Easy)
Category 1: Word Problems > Sets >

Explanation: To answer this question, you'll need the number of tickets sold at full price and at the discount, plus the full price of the tickets as the price of the discounted tickets.

Statement (1) allows you to find the first two: if the number of tickets sold at full price is (1/4) of 400, or 100, leaving 300 sold at a discount. However, it is insufficient because there's no information about the cost per ticket. Statement (2) is also insufficient, as it has no information about the number of tickets at either price.

Taken together, the statements are still insufficient. While we know the number of each type of ticket, and the full price of the ticket, we can't answer the question without knowing the price of the discounted tickets. The correct choice is (E).

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