LSAT 106 | Section 1 | Logical Reasoning: Q3

LR Question 3 Explanation

QUESTION TEXT: For any given ticket in a 1000 ticket lottery, it is…

QUESTION TYPE: Flawed Parallel Reasoning

CONCLUSION: It’s likely that none of the 1,000 tickets will win the lottery.

REASONING: It’s likely that no individual ticket out of the 1,000 will win the lottery.

ANALYSIS: This argument mistakes individual odds and collective odds.

The odds of any one ticket winning are slim. But I wouldn’t say no to a gift of 1,000 free lottery tickets. Odds are cumulative, a large group of tickets has decent odds of winning.

And if it’s the type of lottery where there is always a winner, then one of the 1,000 tickets will certainly win.

___________

1. CORRECT. It’s true that there’s only a 1/13 chance that a random card will be an ace. But if you draw 52 cards, then 4 of them will be aces, on average. This argument mistakes individual and collective odds.
2. This is a good argument. If one horse wins, the others lose.
3. This is a good argument. If it’s not reasonable to believe something will happen, then it’s certainly reasonable to believe it won’t happen.
4. This is a bad argument. It sounds like the coin is a trick coin. If a coin has flipped tails 1,000 times in a row, something isn’t right (even if that is theoretically possible).
5. This is a bad argument. Not everyone is of average height. And five year old girls may have a different average height than boys. So since we know Pat is a girl, it’s not reasonable to believe she is exactly one meter tall.