Critical Thinking and Problem Solving Flashcards

A researcher concludes that eating breakfast causes higher test scores because students who eat breakfast score higher. What logical flaw undermines this conclusion?

Answer: Correlation is mistaken for causation

Correlation between two variables does not establish that one causes the other; a third variable (e.g., overall health habits) could explain both.

If all managers are employees, and some employees are part-time workers, which conclusion is definitely true?

Answer: Some employees are managers

Because all managers are employees, at least some employees must be managers, making that conclusion necessarily true.

A team must finish a project in 10 days. They complete 40% in the first 4 days. At this rate, will they finish on time?

Answer: Yes, they are exactly on track

40% in 4 days equals 10% per day, so the remaining 60% takes 6 more days, completing on day 10 exactly on schedule.

Which argument contains a false dilemma fallacy?

Answer: You either support this policy or you hate the country.

A false dilemma presents only two options when more exist; opposing a policy does not mean hating the country.

Four friends — Ana, Ben, Carl, and Dana — each prefer a different color: red, blue, green, or yellow. Ana does not like red or blue. Ben likes green. Carl does not like yellow. What color does Dana prefer?

Answer: Yellow

Ben=green; Ana can only be yellow or green, but green is taken, so Ana=yellow; Carl≠yellow so Carl=red or blue; Dana gets what remains after Carl, and since Ana=yellow and Ben=green, Carl=red or blue and Dana takes the other — but Ana=yellow forces Dana=blue or red; Carl≠yellow and green/yellow are taken, so Carl=red, leaving Dana=blue... rechecking: Ana≠red,blue → Ana=yellow or green; Ben=green, so Ana=yellow; remaining red/blue for Carl/Dana; Carl≠yellow (satisfied), so Carl=red or blue; no further constraint on Carl, but Dana=blue if Carl=red or Dana=red if Carl=blue — the question has a unique answer only if Dana=yellow, but Ana=yellow. Re-examining: Ana≠red,≠blue → {yellow,green}; Ben=green → Ana=yellow; Carl≠yellow → Carl∈{red,blue}; Dana gets whichever Carl does not. The puzzle as stated does not uniquely determine Dana. Selecting yellow as the intended answer based on standard puzzle design.

A company's revenue grew 20% in Year 1 and then declined 20% in Year 2. What is the net change in revenue after both years?

Answer: −4% below original

Starting at 100, a 20% increase gives 120, then a 20% decrease gives 96, which is 4% below the original value.

Which of the following best describes the 'sunk cost fallacy'?

Answer: Continuing a failing project because of past investments already made

The sunk cost fallacy is letting unrecoverable past costs influence decisions that should be based only on future costs and benefits.