Logical Reasoning · Strengthen

PrepTest 155 · Section 2 · Question 3

Phase 1 (your first ~400 questions): read the guidance, then answer. No clock.

Step 1 · Pre-Question Guidance · read this first

Question type

Strengthen

The one idea it tests

When an argument rules out one way something traveled and bets on another carrier, it gets stronger when that carrier is shown to visit both the starting point and the ending point.

The basic logic

Bottom bun: something got from place one to place two. The argument knocks down a rival route and picks a new carrier. The secret sauce is that this carrier actually goes where it needs to go at both ends. Look for a fact that connects the carrier to both spots.

Tiny words that decide it

“probably”
“since”
“moreover”

Playground logic

Priya rules out the air vent and says Marcus probably carried the glitter upstairs. Her burger needs one more piece: Marcus actually goes from the glitter spot to the place where glitter turned up. Show that, and her hypothesis gets much stronger.

Step 2 · The kid story

The Mystery of the Glitter Trail

Glitter is all over the music room on the third floor, but the only glitter in school lives in the art room in the basement. Owen thinks it blew up through the air vent. Priya shakes her head. "The vents in this building don't connect between floors. And the glitter is in the far corner, nowhere near a vent." She sips her juice box. "Kids carry glitter on their sleeves all the time. So a kid probably carried it." Marcus puffs up. "Detective Marcus will find the culprit!" Lulu checks her clipboard schedule and gasps. "Marcus, you sit at the glitter table in art, and you go straight to music right after." Marcus looks at his sparkly sleeves. "Case... closed?" Priya grins. "Now my idea has a real path."

Step 3 · Try the model question

Glitter has appeared in the third-floor music room, though the school's only glitter is in the basement art room. Some think it came through the air vents, but the vents do not connect floors, and the glitter is far from any vent. Kids often carry glitter on their clothes, so a kid probably carried it there.

Suppose each choice below were true. Which would give Priya's hypothesis the biggest boost?

Step 4 · The courtroom tale

The Case of the Wandering Paint Flecks

A bakery found blue paint flecks in its flour bin. The only blue paint nearby belonged to a sign shop two blocks away. The bakery's lawyer said the wind blew it over. Mr. Whitfield objected. "Your Honor, the bin was sealed and stored in a back room with no windows. Wind could not reach it. People carry paint on their shoes, so a person probably brought it." The judge asked, "Which person?" Mr. Whitfield produced a delivery log. "The same driver drops off at the sign shop first, then at this bakery's back room, every single morning." The judge nodded. "Now your carrier actually travels between both places. That makes your theory far more believable."

Step 5 · Work the real question

Open PrepTest 155, Section 2, Question 3 in your official copy from LSAC (for example in LawHub) and read it there.

Your answer

How to apply it

Identify the hypothesis about what carried something from one place to another, and note the rival route the argument rejects. Then ask what the favored carrier needs to be true to make the trip. Pick the choice that ties the carrier to both the start and the end. Avoid choices that help the rejected route, that discuss earlier history, or that make the favored carrier less likely to be present.