No projects that involve historical restorations were granted building permits this month. Since some of the current ...

Advaith on November 4, 2015

Explanation

Could you please explain this?

Reply

Mehran on November 9, 2015

Let's diagram the stimulus first.

No projects that involve historical restorations (HR) were granted building permits (GP) this month.

HR ==> not GP

Some of the current projects of the firm S&S are historical restorations.

S&S-some-HR

Therefore, at least some of S&S's projects were not granted building permits this month.

This is a valid conclusion that can be drawn by combining the first two premises in a transitive formation, as follows:

S&S-some-HR ==> not GP

Therefore: S&S-some-not GP

Answer choice (D) is identical, although the order of the premises is different. I am going to rearrange them so you can see the logical structure is identical:

None of the films released this season (RTS) were enthusiastically reviewed (ER).

RTS ==> not ER.

Several films directed by Hannah Barker (HBF) were released this season.

"Several" is diagrammed as "some."

HBF-some-RTS

Now, combine these two premises in a transitive formation, as follows:

HBF-some-RTS ==> not ER

Therefore: HBF-some-not ER.

That is identical to the stimulus.

Hope this helps!