Logical reasoning PrepTest 133 · Section 1 · Question 20

Incorrect. Downtown traffic congestion decreasing is a necessary condition of the entire chain, not a sufficient condition for anything else.

Correct. Argument or Facts:
Facts

Question Type:
Must Be True

Stimulus Summary:
(1) More consumers live downtown → Profits of downtown businesses increase
(2) Decrease in downtown cost of living → More consumers live downtown
(3) not Downtown traffic congestion decreases → not Profits of downtown businesses increase

Answer Anticipation:
The stimulus gives us three conditional statements with overlapping terms, so we need to get the diagram right and then see if we can combine them.

The first diagram is straightforward, featuring "if" as our sufficient condition indicator. The second statement is trickier, but if something "will guarantee" an outcome, then that thing is sufficient for the given outcome. Finally, the last statement has "unless," which we treated as "if not" and diagrammed accordingly.

Looking at these statements, they each share a term with another conditional, so we should check to see if we can make a chain with all three. The first two nicely chain together, and the third will once we take the contrapositive:

Decrease in downtown CoL → More consumers live downtown → Profits of downtown businesses increase → Downtown traffic congestion decreases

And its contrapositive:

not Downtown traffic congestion decreases → not Profits of downtown businesses increase → not Decrease in downtown CoL

The correct answer will reflect one of these chains.

Answer Explanation:
This answer is established in our first conditional chain, so even though it doesn't utilize each statement from the stimulus, it's correct.

Key Takeaway:
For Must Be True questions that involve conditional chains, doing all the work up front lets you speed through the answer choices. And, as we always take the chance to do when we can, this question highlights how practice on conditional logic can really help you speed through a question—so practice!

Incorrect. Downtown traffic congestion decreasing is a necessary condition of the entire chain, not a sufficient condition for anything else.

Incorrect. Downtown traffic congestion decreasing is a necessary condition of the entire chain, not a sufficient condition for anything else.

Incorrect. This answer is an illegal reversal of the first conditional statement from the stimulus.