QUESTION TEXT: The photographs that the store developed were …
QUESTION TYPE: Necessary Assumption
CONCLUSION: If the customer’s claim is correct, the store owes a refund.
REASONING: The customer says they handled the film properly. The film and camera worked.
ANALYSIS: Unusual. A necessary assumption question that uses linked conditional reasoning. Usually you shouldn’t diagram necessary assumption questions.
We have these facts:
- Customer says handled correctly (C)
- Camera not defective (
CD) - Film not defective (
FD) not processed correctly➞ refund (PC➞ R)
If the store didn’t process the film correctly, they owe the customer a refund. But the evidence doesn’t lead to improper processing. I’m going to draw the evidence on the left and the conclusion on the right:
C and CD and FD PC ➞ R
The author wrongly assumes they’re connected. To fix the argument, add an arrow connecting left and right. Here’s the missing premise:
C and CD and FD ➞ PC
If PC, then we can conclude ‘R’. Unusually, this answer is sufficient and necessary.
___________
- We’re must prove the store owed a refund. This says what happens if they owed one. Not helpful.
- CORRECT. This links the premises to the conclusion. This has to be true f0r the argument’s reasoning to work. Oddly, it’s also a sufficient assumption.
- The pictures weren’t taken with a defective camera, so this tells us nothing.
- The author talks about what happens if the client handled the film correctly. This is irrelevant.
- Same as D. This question is about what happens if the claim is correct.
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