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Topic: Apocalypto (Read 765 times) |
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alien2
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The story takes place in the 14th century South America. 24 members of a peaceful tribe are running away unarmed from 48 aggressive tribesmen armed with spears, bows and arrows. Jaguar Paw is the leader and the most intelligent one amongst the 24.
They are currently standing at the edge of a river, at the head of the waterfalls. From their standpoint they see 4 similar rocks aligned in direction of the other bank of the river and approximately equally distant from one another. So they divide the river’s flow into 5 almost identical flows. It would be fatal to jump down from these rocks because right below them and between the ends of the waterfalls, there is another set of 4 similar rocks sticking out of the pool of the water.
Blunted says to Jaguar Paw that he remembers vaguely being here before his partial amnesia due to hitting his head. He remembers that there are 3 more rocks down the waterfalls, but below the water’s surface. All of these rocks hidden from the eye are shaped as a rectangular prism, and they all have the same length of 10 m, so that their length is aligned with the river’s flow. He says that the biggest hidden rock is 72 inches wide, which corresponds to average shoulder width of four men, that is, 4 × 18 inches. This rock is either below the 1st waterfall from the right or below the last waterfall from the left. Since maximum 6 people can form a line near the beginning of each waterfall, if 6 men were to jump at the same time down the 1st or the 5th waterfall, and if they are unlucky because the big rock is below the surface, four of them would certainly die since only two would escape the impact. He also remembers regarding the remaining 2 rocks which are below 2 other waterfalls, that one rock is 36 inches wide and the last rock is 18 inches wide. So if 18 men were to jump at the same time down the 3 waterfalls in the middle, 3 of them would certainly die and 15 would survive the fall. Blunted does not remember any other additional details.
Since the aggressive tribe is gaining on them, Jaguar Paw has to come up quickly with a plan and then they must all jump at the same time because time is running out. If they don’t jump, the aggressive tribesmen will eat their hearts. Once again, maximum 6 people can form a line near the beginning of each waterfall, and then all 24 will synchronously run and jump. All who don’t hit one of the mentioned 3 rocks below the surface will survive the fall.
Considering that quick-witted Jaguar Paw will quickly devise a plan to try to save as much lives as he can, what is the maximum number of people which can be saved for certain?
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rmsgrey
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Re: Apocalypto
« Reply #1 on: May 20th, 2015, 7:20am » |
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I can do nineteen.
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alien2
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Re: Apocalypto
« Reply #2 on: May 22nd, 2015, 8:11am » |
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I get 19 too.
I am certain that a wu riddler could make the puzzle more challenging.
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alien2
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Re: Apocalypto
« Reply #3 on: May 28th, 2015, 2:20am » |
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2. Everything is the same except that there are 13 peaceful tribesmen, maximum 5 people can form a line near the beginning of each waterfall and 2 rocks are below the surface. One hidden rock 54 inches wide is below the 1st or the 5th waterfall. The rock 36 inches wide is below one of the 3 remaining waterfalls in the middle. 54 inches correspond to average shoulder width of 3 men and 36 inches correspond to average shoulder width of 2 men.
My advice is that you consider this variant only rather than the original riddle.
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rmsgrey
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Re: Apocalypto
« Reply #4 on: May 28th, 2015, 1:35pm » |
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on May 28th, 2015, 2:20am, alien2 wrote:2. Everything is the same except that there are 13 peaceful tribesmen, maximum 5 people can form a line near the beginning of each waterfall and 2 rocks are below the surface. One hidden rock 54 inches wide is below the 1st or the 5th waterfall. The rock 36 inches wide is below one of the 3 remaining waterfalls in the middle. 54 inches correspond to average shoulder width of 3 men and 36 inches correspond to average shoulder width of 2 men.
My advice is that you consider this variant only rather than the original riddle. |
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eleven
| hidden: | | It seems a little unfortunate not to be able to do better than send everyone down the middle three lanes, though at least there is a chance of no-one getting hit that way. |
Are the rocks' positions discrete or continuous? That is, is each waterfall 5 separate channels, 2 or 3 of which may be blocked, or is it possible for a rock to be offset by half a person and take out 3 or 4 if 5 try jumping down abreast?
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alien2
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Re: Apocalypto
« Reply #5 on: May 29th, 2015, 2:44am » |
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on May 28th, 2015, 1:35pm, rmsgrey wrote:
Your answer is correct.
on May 28th, 2015, 1:35pm, rmsgrey wrote:
Are the rocks' positions discrete or continuous? That is, is each waterfall 5 separate channels, 2 or 3 of which may be blocked, or is it possible for a rock to be offset by half a person and take out 3 or 4 if 5 try jumping down abreast? |
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I guess I wasn't clear enough on that point. I can't explain it sufficiently well, but the rock 54 inches wide can take out maximum 3 men and the rock 36 inches wide can take out maximum 2 men. I guess it would be best to say that there are 4 small pointy rocks sticking out of the river at the beginning of each waterfall and equally distant from one another.
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| « Last Edit: May 29th, 2015, 3:34am by alien2 » |
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