Paraphrase:

Context: Government says nuclear power plants are safe and public's fear is groundless.

P1: Limiting financial liability is justified due to a threat of injury from a nuclear accident.

Conclusion: Thus, fear is well-grounded.

Answer choice D is correct. The principle roughly states that if no real danger, then the government does not act. Or, If the government acts, then there is a real danger. This supports the conclusion that the public's fear is well-grounded.

Paraphrase:

P1: Suggestions for improved efficiency that are from employers are not likely to elicit positive responses.

P2: Employer should engage employee in dialogue that emphasizes the positive contributions of the employee to the development of such ideas.

Conclusion: Ideas that employers want to try will be implemented more quickly and efficiently.

Answer choice C is an incorrect trap answer.

(1) The ideas do not necessarily have to derive from the dialogue. It is consistent with the original premises that an employee can contribute to an idea outside of a dialogue.

(2) The comparison is between suggestions from employers vs suggestions from employees. Answer choice C makes a comparison between ideas from a dialogue where employees participated vs ideas from a dialogue where employees did not participate. Thus, B is correct.

Paraphrase:

P1: Exclusive dependence on speech improves memory. What is useless and irrelevant is quickly irradiated.

P2: Writing has no limits, so it can lead to writer and reader becoming confused.

Conclusion: Oral traditions are preferable to written ones.

How can we get from the premises to the conclusion? We need a premise that supports why we should prefer oral traditions. Answer choice D is the correct answer.

Paraphrase:

One year ago: 50% Discount | 50% Full Fare Ticket

Today: 90% Discount | 10% Full Fare Ticket

Additional Premise: Full price tickets cost the same.

Conclusion: Therefore, on average people pay less.

What about the price discount tickets? We need an assumption that discount tickets have stayed the same. Otherwise, it is possible that average prices have not decreased. So B is the correct answer choice.

Paraphrase:

P1: Most choral preludes were written for organ.

P2: Most great choral preludes were written by Bach.

P3: Bach never expresses his own feelings.

We know that Bach never expresses his feelings in his works. So, C is the correct answer. P3 is not specific to choral preludes so it is impossible for Bach to express feelings in other works.

Paraphrase:

P1: Nearly all mail that is correctly addressed arrives at its destination within 2 days.

P2: Correctly addressed mail takes longer only when it is damaged.

Conclusion: Most mail arrives after 3 days or more.

Assume there are 100 pieces of correctly addressed mail. We know that nearly all of this set (say 90) arrives within two days. Some of this correctly addressed mail does not arrive within two days and must be damaged (10 pieces). However, most mail arrives three business days or more after being sent. That means there must be more than 90 pieces of mail that arrive after 3 days or more. The set damaged mail has only 10 pieces so it must be the case that a large proportion of mail is incorrectly sent.

Note: Mail that is correctly addressed and damaged is a small subset of the set of mail that is correctly addressed. So most mail cannot be correctly addressed and damaged.

Paraphrase:

Claim 1: Country's nuke power plants are entirely safe and fear is groundless.

Claim 2: Limiting liability in case of accidents is justified by need to protect from threat. If threat, then injury claim can be sustained. If injury claim sustained, injury must result from accident.

So, if limited liability is justified then injury must result from accident. This contradicts with Claim 1.

B not A is the correct answer because we don't know that the government's claim about safety is necessarily false. The only thing we know is that the two statements do not match.

Paraphrase:

Context: Amphibians populations declining. Ozone has depleted for last 50 years.

P1: Ozone blocks UV-B.

P2: Amphibians and their eggs are vulnerable to UV-B.

Conclusion: The primary cause of declining amphibians is depletion of ozone.

A does not strengthen the argument. It doesn’t matter if UV-B is the only ray that damages genes because the conclusion is just that the declining ozone layer causes amphibians to die. For example, it doesn’t matter if UV-A or UV-C has an affect on genes since the conclusion is just about the ozone layer generally.

Paraphrase:

Context: Early 19th century houses that are bigger have wooden boards that are narrower than smaller houses.

P1: People with bigger houses had more money.

Conclusion: Floors made out of narrow boards were a status symbol.

We can make an inference that we need more narrow floorboards to cover the same area. B is correct because it shows that narrow floorboards are about the same price for the same length as wide floorboards.

E is incorrect because it doesn’t support the argument. It could be true that many of the biggest houses had more expensive materials doesn’t necessarily mean that the floorboards are a status symbol.

Paraphrase:

Context: Grow-Again proven treatment for reversing baldness.

P1: Exceeding 5 drops does not increase effectiveness.

Conclusion: Manufacturer’s rebate on Grow-Again will not increase sales and would be unprofitable.

Answer choice C is correct. A manufacturer’s rebate might not encourage current buyers to buy more. However, it might attract new customers. Thus, the manufacturer’s rebate will be unprofitable given that the rebate does not attract new users.

Paraphrase:

P1: Average car prices have increased relative to individual income.

Conclusion: Individuals who buy cars today spend a larger amount relative to individual income.

E is correct because it finds an alternative explanation for P1. Average car prices may have increased, but this may be caused by non-individuals who buy cars. For example, corporations might be buying a lot of fancy new cars now driving the average price up.

Paraphrase:

P1: If painters were to make the journey to the islands, they must have needed to eat sea animals.

P2: No paintings unambiguously depict sea animals.

Conclusion: Thus, cave paintings on the islands are not a description of diets.

Answer choice C does not weaken the argument. We don't know if this has anything to do with the diets of the painters and we cannot assume that the painters ate meat on the islands. So, the conclusion is compatible with holding that many paintings depict land animals.

Paraphrase:

P1: Human brain and mental capacities evolved to help self-preservation.

P2: Capacity to make aesthetic judgements is an adaptation.

C: Aesthetic judgements must be evaluated in terms of promoting self-preservation.

Substituting the stimulus in answer choice C, we get the claim that if aesthetic judgement develops to serve self-preservation then the standard by which it must be judged is how well it serves self-preservation. This strengthens the argument because the principle here mirrors the conclusion.

Paraphrase:

P1: Low power circuitry in modern planes is more susceptible to interference.

P2: During landing planes receive signals, and recently one plane veered off course when laptop was turned on.

C: Modern plane navigation are put at risk by electronic devices.

E is correct. The fact that electronic devices became popular alongside modern plane navigation systems does not strengthen the argument that modern plane navigation systems are at risk. For example, E is compatible with the fact that electronic devices don't put navigation systems at risk.

That’s awesome Michael, congrats!

Interested!

Paraphrase:

P1: A greater percentage of red cars are involved with accidents than cars of other colors.

(P2): Red cars cause accidents.

Conclusion: If we ban red cars, we can save lives.

This argument is flawed because there is an alternative cause of the greater percentage of red car accidents. The conclusion relies upon a claim that red cars are not merely correlated, but casually related with accidents. Thus, C is the correct answer.

Paraphrase:

Context: Some argue that higher apes have the capacity for language but have never put it to use.

P1: Linguistic skills gives enormous selectional advantage.

P2: This is like claiming some animal has wings for flight but never thought to fly.

Answer C is the correct answer. The analogy is that a highly useful thing is never utilized. D is incorrect – we have to assume that tobacco is a good thing (not just a thing we want but an advantageous thing). C has a much more reasonable assumption.

Hi everyone, it is actually PT 67 for Sunday. My mistake - sorry about the confusion! We will be going over LR (S2).

If people have already done 68, I’d be happy to also BR that sometime next week.

Note: Need to make a reasonable assumption that the boy would be psychologically harmed.

Paraphrase:

National econ growth → Consumer confidence balanced with small amount of consumer skepticism

Take the contrapositive of this statement. /Consumer confidence balance with small amount of skep → /Econ growth. D is the closest answer choice.

Answer choice A is incorrect because the stimulus only says that when there is consumer confidence and a small amount of consumer skepticism that economic growth can (not will) happen.

Paraphrase:

P1: Economy weak → Prices constant

P2: Economy weak → Unemployment rises → Investment decreases

P3: /Investment decreases

Thus, A is the incorrect answer. Take the first part of the disjunctive in A. Because the contrapositive of P2 and P3 is /Investment decreases → /Economy weak, we know that the economy is not weak. So then look at the second part in A. Investment must be decreasing but we know by P3 that investment is not decreasing.

Note: Think of although as and.

Hi everyone, I will be leading the BR today of PT 65 Section 1 (Logical Reasoning) starting at 7pm.

Please add questions you'd like to go over in the google docs:

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The link to join is:

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Paraphrase:

Context: One approach is to designate as real all and only entities posited by the most explanatorily powerful theory.

Premise: Most scientific theories contain entities posited solely on theoretical grounds.

Conclusion: Approach is wrong.

A missing premise seems to be entities posited on theoretical grounds are not real, which establishes that the theory gets things wrong. Thus, B is the correct answer.

I'm interested!