LSAT Explanation PT 41, S3, Q25: Most serious students are happy students,

LSAT Question Stem

Which one of the following can be properly inferred from the statements above? 

Logical Reasoning Question Type

This is a Must Be True question. 

Correct Answer

The correct answer to this question is B. 

LSAT Question Complete Explanation

This question is a Must Be True (MBT) question, which means we need to find the answer choice that can be properly inferred from the information given in the passage.

First, let's break down the passage and analyze the information:

1. Most serious students are happy students.

2. Most serious students go to graduate school.

3. All students who go to graduate school are overworked.

We can represent this information using formal logic notation:

SS = serious students

H = happy students

GS = go to graduate school

O = overworked

1. Most SS -> H

2. Most SS -> GS

3. GS -> O

Now, let's evaluate each answer choice:

a) Most overworked students are happy students.

We cannot infer this from the given information. We know that some overworked students are happy (since some serious students are both happy and go to graduate school), but we don't know if most overworked students are happy.

b) Some happy students are overworked.

This answer choice is correct. Since most serious students are happy and most serious students go to graduate school, we can infer that some happy students go to graduate school. And since all students who go to graduate school are overworked, we can conclude that some happy students are overworked.

c) All overworked students are serious students.

We cannot infer this from the given information. At best, we can infer that some overworked students are serious students (since most serious students go to graduate school and all students who go to graduate school are overworked). But we cannot say that all overworked students are serious students.

d) Some unhappy students go to graduate school.

We cannot make any inference about unhappy students from the given information.

e) All serious students are overworked.

We can infer that most serious students are overworked (since most serious students go to graduate school and all students who go to graduate school are overworked). However, we cannot say for certain that all serious students are overworked.

Therefore, the correct answer choice is (b) Some happy students are overworked.