[Guest]

Another murder puzzle from a logic book

One evening four explorers named Xavier, Yeoman, Zenger, and Osborn made separate camps along the banks of a river.

Wilson, a fifth explorer camped in the country's interior, communicated with the other men by radio at various times during the night. When he received no reply from Osborn after 10:30 that night, Wilson communicated with the other three men to express his concern.

The next morning Osborn was found dead; he had been murdered.

Evidence at the scene of the crime indicated that the killer had approached Osborn's camp by boat from the river. Xavier, Yeoman, and Zenger had each had access to a canoe on the previous night.

Wilson suspected that either Xavier, Yeoman, or Zenger had killed Osborn. From the following facts, Wilson was able to eliminate two of these men as suspects.

1. Osborn was killed in his camp before 10:30 on the previous night; he had been shot and had died instantly.

2. The killer traveled to Osborn's camp and returned to his own camp by canoe.

3. Xavier's camp was located directly downstream from Osborn's camp, Yeoman's camp was located directly across the river from Osborn's camp, and Zenger's camp was located directly upstream from Osborn's camp.

4. At least 80 minutes were needed for each of the three men to make the round trip to and from Osborn's camp by canoe.

5. There was a strong current in the river.

6. Wilson received replies to his radio calls at the following times:

From Osborn - 9:15

From Xavier - 8:15, 9:40, and 10:55

From Yeoman - 8:20, 9:45, and 11:00

From Zenger - 8:25, 9:50, and 11:05

Which one of the three men could Wilson not eliminate as a suspect?

[Guest]

Xavier can't be ruled out as a suspect.

Yeoman and Zenger both need at least 40 minutes for the return leg of the journey (half of 80, plus longer for Zenger). This means the earliest they could have gotten back from Osborn's camp, had they killed him at 9.15, was 9.55. As they're in touch with Wilson before that, they could not have done it.

Xavier could have required less time for his return journey, so it is possible he could have got back in 25 mins (though we can't be sure). So it's not possible to rule him out as a suspect.

Edited October 15, 2010 by rajat_magic

[Guest]

Xavier can't be ruled out as a suspect.

Yeoman and Zenger both need at least 40 minutes for the return leg of the journey (half of 80, plus longer for Zenger). This means the earliest they could have gotten back from Osborn's camp, had they killed him at 9.15, was 9.55. As they're in touch with Wilson before that, they could not have done it.

Xavier could have required less time for his return journey, so it is possible he could have got back in 25 mins (though we can't be sure). So it's not possible to rule him out as a suspect.

You got it! Good job!

[Guest]

I guess I'm second but here's a

I figure that only Xavier could murder Osborn at/after 9:15 and be back to his camp by the time Wilson talked to him again. He could do this because the strong current in the river would make his return trip much shorter than the trip to Osborn's camp.

[Guest]

If Yeoman was just across the river, couldn't he just have shot Osborn from his campsite? How big is this river?

I think the better weapon of choice is a knife, it's alot more difficult to stab someone across a river.

[Guest]

I think Xavier is the intended answer since the others wouldn't have time to get back to camp, or their radios.

But, if one of the others is quite smart he would kill Osborn, crack open one of Osborn's beers, change the radio frequency/channel to the one he was on (I assume since Wilson had to contact the others to express his concern they were not all on the same channel or they would have heard the unanswered calls to Osborn), then relax until Wilson called before heading home. Better yet, the killer should instigate the contact with Wilson at time that would help him to be ruled out. Wilson would have had no way of knowing that he was talking to the killer in Osborn's own camp. Mwa ha ha haaa

[preflop]

I think Xavier is the intended answer since the others wouldn't have time to get back to camp, or their radios.

But, if one of the others is quite smart he would kill Osborn, crack open one of Osborn's beers, change the radio frequency/channel to the one he was on (I assume since Wilson had to contact the others to express his concern they were not all on the same channel or they would have heard the unanswered calls to Osborn), then relax until Wilson called before heading home. Better yet, the killer should instigate the contact with Wilson at time that would help him to be ruled out. Wilson would have had no way of knowing that he was talking to the killer in Osborn's own camp. Mwa ha ha haaa

It's one thing to kill a guy, but crack open one of his beers! That, my friend, is unforgivable

[Guest]

Another murder puzzle from a logic book

One evening four explorers named Xavier, Yeoman, Zenger, and Osborn made separate camps along the banks of a river.

Wilson, a fifth explorer camped in the country's interior, communicated with the other men by radio at various times during the night. When he received no reply from Osborn after 10:30 that night, Wilson communicated with the other three men to express his concern.

The next morning Osborn was found dead; he had been murdered.

Evidence at the scene of the crime indicated that the killer had approached Osborn's camp by boat from the river. Xavier, Yeoman, and Zenger had each had access to a canoe on the previous night.

Wilson suspected that either Xavier, Yeoman, or Zenger had killed Osborn. From the following facts, Wilson was able to eliminate two of these men as suspects.

1. Osborn was killed in his camp before 10:30 on the previous night; he had been shot and had died instantly.

2. The killer traveled to Osborn's camp and returned to his own camp by canoe.

3. Xavier's camp was located directly downstream from Osborn's camp, Yeoman's camp was located directly across the river from Osborn's camp, and Zenger's camp was located directly upstream from Osborn's camp.

4. At least 80 minutes were needed for each of the three men to make the round trip to and from Osborn's camp by canoe.

5. There was a strong current in the river.

6. Wilson received replies to his radio calls at the following times:

From Osborn - 9:15

From Xavier - 8:15, 9:40, and 10:55

From Yeoman - 8:20, 9:45, and 11:00

From Zenger - 8:25, 9:50, and 11:05

Which one of the three men could Wilson not eliminate as a suspect?

[Guest]

The last times for each don't matter. They only have a time span of 75 min from the second call out.

It was not yeoman. He would have equal times both ways, from 9:15 contact to 9:45 contact is only giving him 30 minutes each way. It has to be at least 40.

Zeng would have been there quickly going downstream to Oswald. If he killed Oswald at 9:16, then he would only have 35 min to row upstream which would have to take at least 41 min.

Xavier had an hour to get there rowing upstream, and he had 34 min to get downstream to receive his 9:40 call. He is the only one that can't be eliminated.