Weekly Challenge
Five original questions for the week of September 28, 2026. No timer. Check each answer as you go.
A school added a daily 10-minute meditation session and saw detention rates fall 25 percent. The principal credits meditation.
Which of the following, if true, most strengthens the principal's claim?
Replication plus a comparison group is strong evidence. D would weaken the claim, and A, C, and E are irrelevant.
The committee rejected the proposal because it was too expensive. But expense alone cannot decide the matter: the committee approved a costlier proposal last year. If cost were the real standard, that one would have failed too.
The argument proceeds by
The speaker turns the committee's own record against it: last year's costlier approval shows cost is not the real standard being applied.
Whenever the highway is under construction, traffic on Main Street increases. Traffic on Main Street did not increase today.
What can be inferred?
Construction always brings more Main Street traffic. No increase today means no construction today. Contrapositive again.
People who own dogs are happier than people who do not, so getting a dog will make you happier.
Which of the following, if true, most weakens the argument?
This reverses the causal arrow. If happy people self-select into dog ownership, the correlation says nothing about dogs causing happiness.
The new tax is supposed to fund road repairs, but the bill lets the money be spent on anything. Without a lock on the funds, drivers will pay more and the potholes will stay. Voters should reject the tax.
The main conclusion is that
The recommendation to reject the tax is the point. The earlier sentences explain why the tax will not fix the roads.
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Last updated October 12, 2026