#8 - The university’s purchasing department is highly efficient overall. We must conclude that each

[Administrator]

Complete Question Explanation

Parallel Reasoning. The correct answer choice is (C).

Answer choice (A):

Answer choice (B):

Answer choice (C): This is the correct answer choice.

Answer choice (D):

Answer choice (E):

This explanation is still in progress. Please post any questions below!

[irelandbryant]

Can someone explain how B is incorrect!

[Jeff Wren]

Hi irelandbryant,

The argument in the stimulus contains a specific flaw that we refer to as an error of division (commonly called a whole-to-part flaw). The way that this flaw is made is when one assumes that what is true of a whole (whether that be a whole organization, team, thing, etc.) must also be true of its individual parts.

A simple example of this flaw would be the argument:

Team X is the best football team in the league. Therefore, the quarterback for Team X must be the best quarterback in the league.

Answer B contains a related (but not identical flaw) that we refer to as an error of composition (commonly called a part-to-whole flaw). This flaw goes in the other direction, when one assumes that what is true of a part of something (whether that be an organization, team, thing, etc.) or even each of the parts individually, must also be true of the whole thing.

A simple example of this flaw would be the argument:

Team Y has the best quarterback in the league. Therefore, Team Y must be the best football team in the league.

Answer B makes this error by going from each member to concluding about the entire department as a whole.

More information on these flaws can be found in lesson 7 of The PowerScore LSAT Course or in chapter 15 of The Logical Reasoning Bible.

[ROMI92]

Hi,

Can you please explain why E is incorrect?

[Rachael Wilkenfeld]

Sure Romi! Answer choice (E) is tempting because it's talking about a department and individuals. It even has a conclusion about the individuals. But it isn't actually an error. The premise here gives a rule about working for the department, then applies the rule. That's acceptable reasoning. It talks about the department as a whole as a way of giving the requirement, not as a way of giving a statement about the whole.

A correctly parallel version of answer choice (E) would say that because there is a driver's license for the department, each individual in the department must have a driver's license.

Hope that helps!

[ROMI92]

Thanks Rachael, I understand now