Reading Comprehension · Science
PrepTest 104 · Section 3 · Passage 3
Questions 15–21
Before you start
Open PrepTest 104, Section 3 in your official copy from LSAC and read the passage for Questions 15–21, using the structure guide below. The passage is not reprinted here.
Structure guide
- P1: describes a puzzling ability, notes that one far-fetched explanation was already tested, and lays out two main candidate explanations
- P2: argues the first candidate is unlikely by citing experiments against two versions of it, then admits a combined test has never been run
- P3: calls the second candidate more promising but still unclear, then presents one researcher's specific version and the evidence offered for it
- P4: raises objections to that version: a failed detection test, a simpler account of the supporting results, and better-controlled results
Step 2 · The kid passage
The Button Under the Cup
Every Sunday, Grandpa hides a button under one of three paper cups, slides the cups around the kitchen table, and asks Lulu to point. She almost always gets it right, and she points within a few seconds. Why? Somebody once guessed that Lulu just reads Grandpa's face, so the family tested that too: Aunt Rosa, who never knew where the button was, ran the game, and Lulu still won. That leaves two main ideas. Maybe Lulu follows every slide of every cup, the way a card dealer's helper follows a shuffle. Or maybe she has a clue sense: some signal that tells her which cup is the special one.
The follow-the-slides idea looks weak. When Grandpa shuffles behind a cereal box, Lulu still wins. When she is blindfolded during the shuffle, she still wins. Nobody has tried a cereal box, a blindfold, and extra-fast shuffling all on one Sunday, though.
The clue-sense idea looks better, but what is the clue? Marcus says it is sound: the button cup makes a tiny rattle, and Lulu has learned that rattle over many Sundays. His proof: when Lulu wears Tommy's scratchy winter earmuffs, she does badly.
There are problems. In one test, Lulu could not tell a rattling cup from a silent one at all. And the earmuffs are itchy and annoying, which could throw anyone off. When Lulu wears soft, comfy headphones that block sound just as well, she wins as usual.
Step 4 · The courtroom tale
The Trial of the Perfect Pie Guess
Judge Penny Marlow frowned at the bakery contest record. A taster named Gus picked the winning pie every year. The prosecutor claimed Gus counted the oven timers. Mr. Whitfield snapped his suspenders. "We hid the timers. Gus still picked right. We muffled the bells. Still right." The prosecutor tried a new theory: Gus smells the winner. "Your proof," Mr. Whitfield said, "is that he guessed badly while wearing a heavy, itchy nose clip. Of course he did! He was miserable. With a gentle filter that blocks smell comfortably, he guesses fine." The judge nodded. "So timer counting is out, and some kind of sense is likely. But which sense? Not proven." Gus took a bow and a slice.