Logic Breakdown

Passage Summary: There are only two types of phone calls on this plan, each with its own price. So, if a call isn't one price, it has to be the other.

Conclusion: Any domestic long-distance call on this plan that is not 10 cents per minute must be 15 cents per minute.

Reasoning: There are only two categories of calls (9-5 and 'other') and each has a specific, distinct price (15c and 10c).

Analysis: The reasoning here is a simple exhaustive binary: everything in the group belongs to either Category A or Category B. Since A costs X and B costs Y, anything that doesn't cost Y must be an A and therefore cost X. To find a parallel, look for an argument that sets up a 'this or that' scenario with no middle ground or third option. The key is the structure: 'Everything is either 1 or 2; 1 is X and 2 is Y; therefore, if it's not Y, it's X.' It's a very rigid, mechanical form of logic.

Passage Stimulus

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21.

The pattern of reasoning in which one of the following arguments is most similar to that in the argument above?

Correct Answer
E
Maps perfectly: If a class involves extensive lab work, then lab (P -> X); otherwise normal (not P -> Y). Thus, if not normal (not Y), then lab (X). That mirrors not Y -> X.
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