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by philipswood 57 days ago
# OPUS 4.7

USER: This is a badly phrased puzzle:

> A farmer has 17 sheep. 9 ran away. He then bought enough to double what he had. His neighbor, who had 4 dogs and 14 sheep, gave him one-third of her animals. The farmer sold 5 sheep on Monday and again the next day, which was Wednesday. Each sheep weighs about 150 lbs. How many sheep does the farmer have?

What do you think are possible answers and why? State assumptions and multiple possible interpretations and indicate why you choose the path you do for each.

MODEL: This is a fun one because the ambiguities compound. Let me walk through the decision points.

*Step 1: 17 sheep, 9 ran away → 8 sheep.* Unambiguous.

*Step 2: "Bought enough to double what he had."* Two readings: - (a) Double his current count (8 → 16). He buys 8. - (b) Double his original count (8 → 17). He buys 9.

I take (a). "What he had" most naturally refers to the present state, not the historical starting count. Result: 16 sheep.

*Step 3: Neighbor gives one-third of her animals.* She has 4 dogs + 14 sheep = 18 animals. One-third = 6 animals. Now the ambiguities multiply: - (a) She gives 6 sheep (farmer is a sheep farmer; dogs would be a weird gift). → 16 + 6 = 22. - (b) She gives a proportional mix: 6 × (14/18) = 4.67 sheep, 1.33 dogs. Non-integer, so this is unphysical unless we round. - (c) She gives 6 animals of her choice, unspecified. Underdetermined. - (d) Only sheep count, so it's one-third of 14 = 4.67. Also non-integer.

I take (a). It's the only interpretation that yields a clean integer and matches the puzzle's apparent intent (we're tracking sheep). Result: 22 sheep.

*Step 4: "Sold 5 on Monday and again the next day, which was Wednesday."* This is the deliberately broken bit. Monday's next day is Tuesday, not Wednesday. Options: - (a) Trust "Monday" and "next day" — sold on Mon and Tue. 10 sheep gone. → 12. - (b) Trust "Monday" and "Wednesday" — sold Mon and Wed (skipping Tue). 10 sheep gone. → 12. - (c) Treat the contradiction as invalidating one sale. → 17. - (d) Treat the whole step as unparseable and skip it. → 22.

Either (a) or (b) gives 12, and both agree the farmer sold 10 sheep total — the day-name contradiction doesn't actually change the count. I'd go with that: *12 sheep*.

*Step 5: "Each sheep weighs 150 lbs."* Irrelevant to the count. Red herring designed to make you doubt yourself.

*My answer: 12.*

But the honest answer is that any number from 12 to 22 is defensible depending on how charitable you are to the puzzle's wording. The 150 lbs is a tell — whoever wrote this is testing whether you'll get distracted by noise. The Monday/Wednesday contradiction is probably also a deliberate red herring, since both readings collapse to the same count.