Weekly Challenge
Five original questions for the week of August 3, 2026. No timer. Check each answer as you go.
A local newspaper reported that the city's new bike-share program launched in March, and that bike thefts rose 20 percent from March to September. The editorial concluded that the bike-share program caused the rise in thefts.
The reasoning above is most vulnerable to criticism on the grounds that it
The editorial sees two trends move together and assumes causation. Warm weather could explain both the launch timing and the theft rise.
Maple Street Bakery switched to organic flour in January. Since then, its daily sales have risen 30 percent. The owner believes the organic flour caused the increase.
Which of the following, if true, most strengthens the owner's conclusion?
If customers say the organic flour is why they came, that directly ties the cause to the effect. A would weaken the claim instead.
Every student in the honors program studies at least three hours a day. Maya is in the honors program, and she studies exactly two hours a day.
Which of the following can be properly inferred from the statements above?
The first claim says every honors student studies at least three hours, but Maya is an honors student who studies two. Both cannot be true.
Some people argue that small towns should not build public transit systems, since ridership is always low at first. But every successful system started small. The question is not whether a town needs transit now, but whether it will need it in twenty years.
Which of the following is the main point of the argument?
The speaker's conclusion is the last sentence: the decision should turn on future need, not early ridership. The rest supports that point.
The city plans to reduce traffic by adding a lane to the highway. Officials say the extra capacity will let the same number of cars move faster.
Which of the following is an assumption on which the officials' plan depends?
If the new lane draws more cars, the "same number of cars moving faster" claim falls apart. Negation test: if cars do increase, traffic is not reduced.
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Last updated October 12, 2026