Friday puzzle -- setting the clock

3/12/10, 4:01 PM #1

Alex Y
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Friday puzzle -- setting the clock

Alex Y

This is said to have been done by Immanuel Kant:

One day, his clock had run down, and with his watch in for repair, he had no way to set the time correctly. That night, he was to have dinner with a friend. To be safe, he left at a time that he was certain would bring him to his friend's house early, and walked his regular route to his friend's house. When he got there, he noted the time on the clock in his friend's hallway. After dinner and conversation, his said his goodbyes, walked back home and correctly set his clock.

How did he correctly set the time on his clock?

Re: Friday puzzle -- setting the clock

3/12/10, 5:00 PM #2

Dan Donaldson
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Re: Friday puzzle -- setting the clock

Dan Donaldson

I will try this:

Set his clock to 12:00 just before he leaves. Note the time when he gets to his friend's house, and again when he leaves. That way he knows how long he spent at the friend's. When he gets home, the time on his clock will be the total time he was gone. If we subtract the amount of time he was at the friend's, the remainder is the walk to and from that house. If we assume he walks at a constant pace, then half of that would be the walk time. The time at the friend's house Plus the time when he arrived there plus the walk time would be the correct time.

Clear as mud?

- - -

I have been woodworking for about 25 years now, and would consider myself an enthusiastic amateur. My claim to fame (or infamy) has always been fixing stuff. I spent time in the Air Force in the 60's then went to work as an electronic technician for civil service. I finally got my EE, and being fed up with the civil service nonsense, took a job with Ford Motor Company until I went with the split to Visteon last year. I got interested in music and started playing in a bluegrass band. I wanted a new guitar, and that kind of led me into woodworking. I bought some books, a few tools, and built a guitar. Luckily, I didn't know any better than to try that as a first ever project. I still play it when I get a chance, so it must not be too bad if it can live for over 20 years. After a stint in Mexico for my job, I moved into a new house and built a small shop. Since then I have been collecting tools and skills, probably more of the former than the latter ;-). Finding this site has done more for my skills and enjoyment than anything else. I have learned a lot and really enjoy the friendships that I have made here. I have been married to LOML (Lori) for 32 years now and have 6 kids. When they are all gone, I want to get a 1 bedroom house (so there is not room for them to move back in) and at least a 6 car heated/air conditioned garage for a shop. (Dream on...)

Re: Friday puzzle -- setting the clock

3/12/10, 5:32 PM #3

Alex Y
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Re: Friday puzzle -- setting the clock

Alex Y

That was too easy? I didn't find it so

Re: Friday puzzle -- setting the clock

3/13/10, 5:25 AM #4

Dan Donaldson
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Registered: 9/17/01

Re: Friday puzzle -- setting the clock

Dan Donaldson

Is it correct? If so, this is just one of those things that happen make sense to me. Some of the puzzles just don't click at all. For others such as this one, for some reason, the solution I got just came to mind. I did make an assumption not stated in the question, that his walk to and from his friend's house always took the same amount of time. If that is not correct, then this solution won't work.

- - -

I have been woodworking for about 25 years now, and would consider myself an enthusiastic amateur. My claim to fame (or infamy) has always been fixing stuff. I spent time in the Air Force in the 60's then went to work as an electronic technician for civil service. I finally got my EE, and being fed up with the civil service nonsense, took a job with Ford Motor Company until I went with the split to Visteon last year. I got interested in music and started playing in a bluegrass band. I wanted a new guitar, and that kind of led me into woodworking. I bought some books, a few tools, and built a guitar. Luckily, I didn't know any better than to try that as a first ever project. I still play it when I get a chance, so it must not be too bad if it can live for over 20 years. After a stint in Mexico for my job, I moved into a new house and built a small shop. Since then I have been collecting tools and skills, probably more of the former than the latter ;-). Finding this site has done more for my skills and enjoyment than anything else. I have learned a lot and really enjoy the friendships that I have made here. I have been married to LOML (Lori) for 32 years now and have 6 kids. When they are all gone, I want to get a 1 bedroom house (so there is not room for them to move back in) and at least a 6 car heated/air conditioned garage for a shop. (Dream on...)

Re: Friday puzzle -- setting the clock

3/15/10, 12:28 PM #5

Alex Y
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Re: Friday puzzle -- setting the clock

Alex Y

Yes, your answer was correct. And your assumption was better justified by the full statement of the puzzle as I originally saw it, which went into some length about how Kant was known to have very regular habits, such that everyone in the town set their clock by when he appeared on his daily walks, and that his walking to and from his friend's house was at his very steady and constant pace.

I shortened it for retyping here, but your assumption was justified.

Friday puzzle -- setting the clock

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