Logical Reasoning · Must Be True

PrepTest 139 · Section 1 · Question 21

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

Step 1 · Pre-Question Guidance · read this first

Question type

Inference (Must Be True)

The one idea it tests

Stack two facts: one group made many worthy things, and that group acts from one motive only. So that motive is behind many worthy things.

The basic logic

Combine the statements like puzzle pieces. Only accept what the lunchbox already holds; reject anything stronger, any comparison not given, and anything about how often.

Tiny words that decide it

“alone”
“many”
“must”
“unlike”

Playground logic

Priya's lunchbox holds two pieces: home crafters made many amazing projects, and home crafters craft only for fun. Snap them together and you get a safe bite: fun alone is behind many amazing projects.

Step 2 · The kid story

The Craft Fair Ribbons

At the school craft fair, every kid who won a ribbon made something amazing, and most ribbon winners come from art club. Nadia raises her hand. "Kids who craft at home, not in art club, have made lots of amazing things too." Owen adds, "Art club kids often craft for extra credit or to get their names in the newsletter. Home crafters do it just for fun." Marcus jumps up. "So home crafters are better! And art club kids hate crafting!" Priya opens her lunchbox. "Let's only take what's in here. Home crafters made many amazing things. Home crafters do it only for fun. So fun alone is behind many amazing things." Marcus sits. "That's all?" "That's all we can be sure of."

Step 3 · Try the model question

Every ribbon winner at the craft fair, most of them art club members, made an amazing project. Kids who craft at home have also made many amazing projects. And unlike art club members, who often craft for extra credit or attention, home crafters craft purely for fun.

If these statements are true, which one of the following must also be true?

Step 4 · The courtroom tale

The Pie Contest Hearing

Judge Okafor hears three statements in a pie contest dispute. A baker testifies: "Every blue-ribbon pie was excellent, and most came from professional bakers." A neighbor adds: "Home bakers have made many excellent pies too." A third witness says: "Professionals bake for money. Home bakers bake purely for joy." Mr. Whitfield stands. "Your Honor, I won't claim home bakers are better, or that professionals feel no joy. Nobody said that. I only ask the court to note what follows: joy alone has produced many excellent pies." The judge nods. "That much is locked in by the testimony. Anything more would be guessing." Mr. Whitfield bows, happily hungry.

Step 5 · Work the real question

Open PrepTest 139, Section 1, Question 21 in your official copy from LSAC (for example in LawHub) and read it there.

Your answer

How to apply it

Read each statement and list them as separate facts. Look for two that share a group, so they can snap together. Then test each choice: does the lunchbox force it, or does it add a ranking, an 'all', a 'never', or a guess about likelihood? Cross off anything that goes beyond the given facts. The winner simply combines two facts into something smaller and safer.