Logic Challenge #2 - Dogs and Kids

[noah]

Here's an explanation - but feel free to post your own or any questions you might have.

dogs & kids solution.pdf

(84.36 KiB) Downloaded 2195 times

[rdokoye]

Excellent, answers to the questions accompanied by breakdowns, makes it easier to swallow.

[vandbenj]

I thought I'd just add the reason why (A) could be false in Question 3, since I had some trouble seeing it at first.

1. V cannot own the same number and breed of dogs as ANY other kid since V is the only kid that can (and must) own all three dogs
2. U cannot own the same number and breed of dogs as S nor T since U must own 2 dogs and S,T must each own 1 dog
3. If U is to own the same number and breed of dogs as R, R must own exactly 2 dogs
4. Therefore, just as U and S, together, own all three dogs, R and T must, together, own all three dogs.
5. If T owns dog X, then R must own dogs Y and Z
6. If U and R are to own the same number and breed of dogs, then U must also own dogs Y and Z.
7. But this means S must own dog X (just as T does), which is impossible given the added premise.
8. And given the added premise S and T cannot have the same number and breed of dogs.
9. Therefore only R and S could have the same number and breed of dogs (namely, the same one dog):

R: X --
S: X -- --
T: Y -- --
U: Y Z --
V: X Y Z

[AnthonyS543]

Thanks, great questions!

[AlexY297]

Hello, where is the open board covered in the course? Thank you, Alex