Traffic engineers have increased the capacity of the Krakkenbak Bridge to handle rush–hour traffic flow. The resultan...

Connor on February 10 at 12:15AM

Why is C and E Incorrect?

What makes these answers wrong and B correct?

Reply

Ross on February 10 at 08:01PM

There are two sufficient condition keywords (“had the city not,” “”if”) in this Must Be True question, making diagramming the best approach to find the right answer. The two parts of the second sentence can be diagrammed as:

Didn’t Invest in Computer Modeling Tech ? Didn’t Increase Rush-Hour Traffic Flow
Didn’t Increase Rush-Hour Traffic Flow ? Wouldn’t Solve City’s Financial Predictament

Using the transitive property of “Didn’t Increase Rush-Hour Traffic Flow,” these statements can be combined to draw the conclusion that:

Didn’t Invest in Computer Modeling Tech ? Wouldn’t Solve City’s Financial Predictament

And we can take the contrapositive of that conclusion:

Solve City’s Financial Predictament ? Invest in Computer Modeling Tech

The correct answer is a restatement of the original conclusion (Didn’t Invest in Computer Modeling Tech ? Wouldn’t Solve City’s Financial Predictament)

(A) is incorrect becuase we don’t know that choosing this specific computer modeling technology was necessary. The passage only told us that investing in some computer modeling technology was necessary
(C) is also incorrect Just because the bridge can handle more rush-hour traffic doesn’t mean the bridge definitely has more traffic in general.
(D) is incorrect because, like (C), this asserts that there is more rush-hour traffic on the bridge. The bridge has the capacity to handle more rush-hour traffic, but that doesn’t mean there is more rush-hour traffic.
(E) asserts a cause-and-effect relationship between the mayor’s decision and the bridge. But we have no idea what inspired the mayor to demand that the city invest in the technology. Conditional relationships do not imply cause-and-effect relationships.