Logical reasoning PrepTest 102 · Section 2 · Question 13

Incorrect. While Senegalese gold was never refined and thus all had the same proportion of gold, there's no indication that all of the coins had the same weight. Some of the coins could have been bigger than others.

Correct. Argument or Facts:
Facts

Question Type:
Must Be True

Stimulus Summary:
Medieval Spain gold coin-most-Gold from West Africa/Senegal
Senegalese gold vs. other gold:
(1) 92% pure (purest known)
(2) Didn't need refining
(3) Can be recognized by gold content
Other gold - Could be refined above 92% pur
Senegalese gold - Never refined

Answer Anticipation:
This stimulus is all about two things: the comparison between Senegalese gold and other gold, and the strong statements made.

There are several points of comparison—Senegalese gold was the purest and was "never" refined; other gold was less pure, but was refined and could be refined to be purer than 92%.

It's unclear what direction the correct answer is going to take based on all these details as there aren't really many statements that build together to lead to inferences, but identifying these key statements and points of comparison should help us quickly analyze each answer.

Answer Explanation:
The stimulus establishes that Senegalese gold—at 92% gold—was the purest known gold. It also establishes that mints refined and produced coins from other locations, and that gold must have been less pure. As such, this answer is supported by the stimulus and is thus correct.

Key Takeaway:
There are plenty of Must Be True questions that don't have great anticipations. When this is the case, focus on identifying key statements—here, comparisons; strong statements—that frequently lead to correct answers in this question type, and then head straight to the answers.

Incorrect. There's no discussion of the monetary value of any coins, so this answer is out of scope.

Incorrect. While the mints refined some gold to a purer gold content than 92%, there's no indication that they raised all gold to this level to mint. It's possible that some gold was refined to a lower level.

Incorrect. The stimulus does note that the 92% gold content allowed coins to be minted without refining the gold, but that doesn't mean that gold had to be at least 92% pure to be minted without refining. To see why, think about this situation—Winning the billion-dollar lottery allowed Janna to buy a mansion. This doesn't mean that someone who didn't win the billion-dollar lottery couldn't buy a mansion!