im right u idiot
A detective says:
"The suspect's fingerprints were found on the broken window. Therefore, the suspect must have entered through that window."
Which part of the statement is the conclusion?
A. The suspect's fingerprints were found on the broken window.
B. The suspect must have entered through that window.
C. The window was broken.
D. The detective should probably watch fewer crime shows.
B
The conclusion is what the speaker is trying to prove. The fingerprint evidence is the premise used to support it.
A city installs more streetlights downtown. Six months later, nighttime crime decreases. The mayor concludes that the new streetlights caused the decrease.
Which fact would MOST strengthen the mayor's conclusion?
A. Nearby cities that did not install new streetlights saw no similar decrease in nighttime crime.
B. Residents say the new lights make downtown look nicer.
C. The city also repainted several crosswalks.
D. The mayor celebrated by buying everyone sunglasses.
A
A strengthens an argument by ruling out other explanations. The other choices are either irrelevant or don't connect the lights to the drop in crime.
A police officer says:
"Ever since the new coffee shop opened across the street from the station, officers have responded to more calls. Therefore, the coffee shop is causing more crime."
What is the biggest flaw in this reasoning?
A. It assumes that because two things happened around the same time, one caused the other.
B. It doesn't mention what kind of coffee the shop serves.
C. It proves the coffee shop caused the increase.
D. It should interview more police officers.
A
Just because two events occur together doesn't mean one caused the other. There could be many other reasons for the increase in calls.
A judge says:
"To serve on this jury, you must be at least 18 years old."
Which statement must be true?
A. Anyone under 18 cannot serve on the jury.
B. Everyone over 18 serves on the jury.
C. Everyone over 18 wants to serve on the jury.
D. The judge celebrated every juror's 18th birthday.
A
Being at least 18 is necessary. If you're younger than 18, you're automatically out—but being over 18 doesn't guarantee you'll be on the jury.
During a trial, a witness says:
"I either saw the suspect leave the bank, or I saw the suspect enter the jewelry store—but I couldn't have seen both."
Later, security footage proves the witness did see the suspect leave the bank.
What must be true?
A. The witness did not see the suspect enter the jewelry store.
B. The suspect robbed the bank.
C. The witness was lying about everything.
D. The witness should probably schedule an eye exam.
A
The witness said it was one or the other, but not both. If one happened, the other couldn't have.
An attorney argues:
"The witness changed her story three times. Therefore, the jury should be cautious about relying on her testimony."
Which statement is the premise?
A. The jury should be cautious.
B. The witness changed her story three times.
C. The witness is lying.
D. The judge forgot to bring coffee.
B
Explanation
A premise is evidence offered in support of the conclusion. We know the witness changed her story; that fact is used to justify the recommendation.
A lawyer argues:
"Since our office switched to digital case files, attorneys finish cases more quickly. Therefore, using digital files makes attorneys more efficient."
Which fact would MOST weaken the argument?
A. The office hired three additional paralegals at the same time it switched to digital files.
B. Most attorneys enjoy using computers.
C. Digital files are easier to organize than paper files.
D. One attorney still prints every single email.
A
If another major change happened at the same time, that alternative explanation weakens the claim that digital files caused the improvement.
A defense attorney argues:
"Every guilty defendant I've represented admitted to being at the crime scene. Jordan admitted to being at the crime scene. Therefore, Jordan must be guilty."
What is the flaw?
A. It assumes that everyone who admits being at the crime scene is guilty.
B. It ignores eyewitness testimony.
C. It uses emotional language instead of facts.
D. It forgot to ask the judge for a lunch break.
A
The attorney has confused a necessary condition with a sufficient condition. Being at the scene doesn't automatically mean someone is guilty.
A law school says:
"Anyone who earns a full scholarship has an LSAT score of at least 170."
Which statement could be true?
A. A student scored 175 but did not receive a full scholarship.
B. A student received a full scholarship with a 164 LSAT.
C. Every student who scores 170 receives a full scholarship.
D. The admissions office chooses scholarship winners by playing rock-paper-scissors.
A
The rule only goes one way: Scholarship → 170+ LSAT. It does not say that everyone with a 170 gets a scholarship.
A detective says:
"If Jordan is innocent, then Casey committed the burglary."
New evidence proves Casey did not commit the burglary.
What follows?
A. Jordan cannot be innocent.
B. Jordan definitely committed the burglary.
C. Nobody committed the burglary.
D. The detective owes Casey an apology... and maybe some cookies.
A
This is the contrapositive:
If Jordan is innocent → Casey did it.
Casey didn't do it → Jordan isn't innocent.
That doesn't tell us Jordan is guilty—just that we can't conclude innocence from that rule.
A prosecutor argues:
"The defendant's phone was near the crime scene when the robbery occurred. Therefore, the defendant committed the robbery."
Which assumption is the argument making?
A. Being near the crime scene makes someone suspicious.
B. The defendant's phone could not have been there without the defendant also being there.
C. The robbery happened at night.
D. Cell phones secretly enjoy solving crimes.
B
The conclusion depends on linking the phone's location to the defendant's location. If someone else had the phone, the argument becomes much weaker.
A detective says:
"Every witness described the getaway car as red. Therefore, the robber must have driven a red car."
Which fact would MOST strengthen the detective's conclusion?
A. Security camera footage also shows a red car leaving the scene immediately after the robbery.
B. One witness likes the color red.
C. The robber has been seen driving blue cars in the past.
D. The detective's favorite car is also red.
A
Independent evidence confirming the witnesses' descriptions makes the conclusion much more believable.
A prosecutor says:
"Every witness agreed the getaway car was black. Therefore, everything the witnesses said must be accurate."
What is the flaw?
A. It assumes that being correct about one fact means the witnesses are correct about everything.
B. It should have questioned more witnesses.
C. It relies on fingerprints instead of testimony.
D. It forgot to ask what kind of car it was.
A
Someone can be right about one detail and wrong about another. The argument overgeneralizes from a single point of agreement.
A detective says:
"If the alarm was working, then the security office received a signal."
Which statement must be true?
A. If the security office did not receive a signal, then the alarm was not working.
B. If the security office received a signal, then the alarm was working.
C. The alarm definitely went off.
D. The batteries were changed last Tuesday.
A
This is the contrapositive, which is always logically valid. The other answers reverse or add information that isn't supported.
A prosecutor says:
"Every person who entered the vault used a keycard."
Security records show Taylor used a keycard.
Which statement is best supported?
A. Taylor may have entered the vault, but we can't be sure.
B. Taylor definitely entered the vault.
C. Taylor stole something from the vault.
D. Taylor has excellent taste in keycards
A
Using a keycard is necessary for entering the vault, but not everyone who uses a keycard necessarily enters the vault.
A defense attorney says:
"No DNA from my client was found at the crime scene. Therefore, my client is innocent."
Which answer best describes the argument?
A. It assumes that guilty people always leave DNA behind.
B. It proves the client is innocent.
C. It shows DNA is never useful evidence.
D. It demonstrates that crime scene investigators deserve a raise.
A
The attorney is assuming that if the client were guilty, DNA would necessarily be found. That's a strong assumption—and not always true.
A judge says:
"Our courthouse introduced online scheduling last year, and missed court appearances have dropped. Therefore, online scheduling reduced missed appearances."
Which fact would MOST weaken this conclusion?
A. The court also began sending automatic text-message reminders shortly before each hearing.
B. Most attorneys say online scheduling is convenient.
C. Other courthouses are considering online scheduling.
D. The courthouse Wi-Fi is still terrible.
A
Text reminders provide another plausible reason why fewer people missed court, making the judge's conclusion less convincing.
A detective says:
"The suspect refused to answer questions. Innocent people have nothing to hide. Therefore, the suspect must be guilty."
What is the flaw?
A. It assumes that refusing to answer questions is proof of guilt.
B. It doesn't explain what crime occurred.
C. It doesn't mention whether a lawyer was present.
D. It should have offered the suspect a snack first.
A
The detective treats silence as evidence of guilt, ignoring that innocent people may stay silent for many reasons.
A prosecutor says:
"Anyone convicted of this crime must have been at the scene."
Alex was at the scene.
What can you conclude?
A. Alex must have committed the crime.
B. Alex could be innocent.
C. Alex has already been convicted.
D. Alex probably stopped for coffee first.
B
Being at the scene is necessary, not sufficient. Many innocent people could have been there.
Four jurors are discussing a case.
Juror A: "The defendant looked nervous, so they're guilty."
Juror B: "One eyewitness identified the defendant, so the case is over."
Juror C: "The fingerprints, security footage, and phone records all point to the defendant."
Juror D: "My gut has never been wrong."
Whose reasoning is the strongest?
A. Juror A
B. Juror B
C. Juror C
D. Juror D
C
Juror C relies on multiple independent pieces of evidence. The others jump to conclusions based on weak or incomplete reasoning.
A detective says:
"Every person seen leaving the bank wore a blue jacket. Alex was wearing a blue jacket. Therefore, Alex must have left the bank."
What is the biggest problem with this reasoning?
A. It mistakes a condition that is required for one that is enough.
B. It relies on emotional language.
C. It attacks Alex's character.
D. It should have checked whether the jacket was fashionable.
A
The detective has confused necessary and sufficient conditions. We only know that leaving the bank required wearing a blue jacket—not that everyone wearing a blue jacket left the bank.
A prosecutor argues:
"Every time Officer Lee testifies, juries return guilty verdicts. Therefore, Officer Lee's testimony causes juries to convict."
Which fact would MOST weaken the prosecutor's reasoning?
A. Officer Lee is usually assigned to the strongest cases with the most evidence.
B. Officer Lee has testified for over 15 years.
C. Jurors generally find Officer Lee to be polite.
D. Officer Lee drinks way too much coffee before court.
A
This is a classic correlation vs. causation issue. If Officer Lee typically works only the strongest cases, the strength of the evidence—not the testimony itself—could explain the guilty verdicts.
A judge says:
"The last three juries convicted defendants wearing red ties. Therefore, wearing a red tie makes juries more likely to convict."
What is the flaw?
A. It draws a broad conclusion from a very small amount of evidence.
B. It doesn't explain why the ties were red.
C. It assumes juries dislike formal clothing.
D. It forgot to ask whether the ties matched the suits.
A
Three cases are nowhere near enough to establish a reliable pattern. The argument jumps to a sweeping conclusion based on an extremely limited sample.
A defense attorney says:
"If a confession was coerced, then it cannot be used at trial."
A confession was used at trial.
What must be true?
A. The confession was not coerced.
B. The confession proves the defendant is guilty.
C. The defendant confessed voluntarily.
D. The prosecutor bought donuts for the office.
A
If Coerced → Not Admissible, then the contrapositive is Admissible → Not Coerced. That's the only conclusion we can guarantee.
The judge gives the following instruction:
"If the jury finds the defendant guilty, then the verdict must be unanimous."
The jury's verdict was not unanimous.
Which conclusion must be true?
A. The jury did not find the defendant guilty.
B. The jury found the defendant not guilty.
C. The jury was deadlocked.
D. Someone forgot to bring snacks to deliberations.
A
This is another contrapositive:
Guilty → Unanimous
So:
Not Unanimous → Not Guilty (verdict).
Notice that doesn't necessarily mean the jury reached a not guilty verdict—they could have hung. But it does mean they did not return a guilty verdict, making A the only statement that must be true.