LSAT Explanation PT 36, S3, Q21: Sandy: I play the Bigbucks lottery—that's

LSAT Question Stem

Which one of the following most accurately describes a mistake in the reasoning of one of the two speakers? 

Logical Reasoning Question Type

This is a Flaw question. 

Correct Answer

The correct answer to this question is B. 

LSAT Question Complete Explanation

First, let's break down the argument in the passage. Sandy and Alex are discussing when it's best to play the Bigbucks lottery. Sandy believes it's best to play after a few weeks with no winners because the money pot increases each week there's no winner. This is Sandy's conclusion, and the premise is that the money pot increases each week without a winner.

Alex disagrees and argues that one is more likely to win when the money pot is small because fewer people are playing. Alex's conclusion is that it's better to play when the pot is small, and the premise is that fewer people play when the pot is small.

To make this discussion more relatable, let's use a simple example. Imagine a jar of jellybeans. If there are more jellybeans in the jar, it's more appealing to try and guess the number of jellybeans to win the jar. However, Alex argues that when there are fewer jellybeans, there are fewer people guessing, so your chances of winning are higher.

An "Evaluate" question for this argument could be: "Do the number of people playing the lottery affect the odds of winning?"

Now, let's analyze the answer choices:

a) Sandy holds that the chances of anyone's winning are unaffected by the number of times that person plays.

- This answer choice is incorrect because Sandy's argument doesn't mention the number of times a person plays.

b) Alex holds that the chances of Sandy's winning are affected by the number of other people playing.

- This is the correct answer choice. Alex's mistake is thinking that the number of people playing affects the odds of winning, which is not true in a lottery.

c) Sandy holds that the chances of anyone's winning are unaffected by the size of the pot.

- This answer choice is incorrect because Sandy's argument is about playing when the pot is bigger, not about the chances of winning being affected by the pot size.

d) Alex holds that the chances of Sandy's winning in a given week are unaffected by whether anyone has won the week before.

- This answer choice is incorrect because Alex's argument is based on the number of people playing the lottery, not whether someone has won the week before.

e) Sandy holds that the chances of there being a winner go up if no one has won the lottery for quite a while.

- This answer choice is incorrect because Sandy doesn't argue that the chances of winning go up when there's no winner for a while, just that the pot increases when there's no winner.