PT60, S1, Q21 - Each of the candidates

[cyruswhittaker]

Can you please go over the formal logic in this question?

I believe the error lies in that we cannot derive that most candidates are competant managers. Even though each candidate is a small business owner and most small business owners are competant managers, the group size of candidates to small business owners might not fall in that of competant managers, so we can't derive an inference from this.

However, if it was reversed (most candidates are small business owners, we would be able to derive an inference).

Is this correct?

Any clarification would be greatly appreciated. Thanks!

[ManhattanPrepLSAT1]

That's exactly right.

I would add that it would need to be not just that most candidates are small business owners, but also that all small business owners are competent managers.

That in conjunction with the final premise that all competent managers have the skills needed to be mayor, would allow the conclusion in the stimulus to be validly drawn.

Conceptually..

A most B
B ---> C
-----------
yields the inference, A most C

A ---> B
B most C
-----------
yields no inference


Remember, when combining quantified statements with all statements that the similar term between the two statements needs to appear in the sufficient condition of the all statement. Otherwise, no inference can be drawn.

Does that help clear up your question here?

[cyruswhittaker]

Yes, it does, and thank you for mentioning this rule that the common term must appear as a sufficient condition. I can see now how it can be quickly applied to both "most" and "some" statements.