PrepTest 151, Section 2, Question 23

What we’re looking for

Working the answers

• A

  This turns something that sometimes happens into something that will happen to anyone in the stated situation. Some people eventually liking a previously disliked food doesn't guarantee that you will. That is a flawed jump from a possibility or occasional pattern to a guarantee. It doesn't reproduce either the missing-quantity comparison or the inference from repeated consumption to a preference.

• B

  This is tempting because it combines a per-item comparison with an overall conclusion. Reading a book takes longer than watching an episode, yet we don't know how much reading or viewing people actually do. Someone could own many unread books while using one television to watch episode after episode.

  But notice the quantities being counted: books and television sets, not books read and episodes watched. The number of devices doesn't tell us how many viewing sessions occur. B has a problem with its measure of activity, whereas the drink argument compares the contribution of equal amounts of ingredients and overlooks the amounts actually used. Keep B in mind, but look for a closer match to that specific mistake.

• C
  Correct

  Map the pieces. Joe's penny-filled piggy bank corresponds to the sugar-sweetened drink; Maria's nickel-filled bank corresponds to the aspartame-sweetened drink. A nickel contributes more money per coin, just as aspartame contributes more sweetness per gram. But we don't know the number of coins, just as we don't know the amount of sweetener.

  Suppose Maria has five nickels, worth 25 cents, while Joe has 100 pennies, worth a dollar. The more valuable kind of coin produces the smaller total because there are fewer coins. Likewise, less of the stronger sweetener need not produce a sweeter drink.

  C doesn't include the later preference claim, which may initially make it feel incomplete. It does, however, closely reproduce a flaw actually present in the argument. The question asks for the most similar flawed reasoning; a faithful match to that mistake matters more than a merely similar topic.

• D

  This looks like it might capture the second problem: weather exposure and a preference for that weather. But check which one is evidence and which one is the conclusion.

  The original starts with exposure—regularly drinking the sweetened drinks—and predicts a preference. D starts with the preference—Stephanie likes hot weather more—and infers earlier exposure while growing up. It reasons in the opposite direction. That is why D doesn't match the preference flaw, even though the same general ideas appear. C remains the close match to the original's first flaw.

• E

  This assumes that someone's own commute determines the estimate they will make about other people's commutes. Guillermo could know that his drive is unusually short and adjust his estimate accordingly; Abdul could also use information beyond personal experience. E overlooks what the people know about others. It doesn't compare per-unit contributions without their quantities or infer a developing preference from repeated exposure.