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Fatalis
July 27th, 2012, 07:33 PM
Ten people land on a deserted island. There they find lots of coconuts and a monkey. During their first day they gather coconuts and put them all in a community pile. After working all day they decide to sleep and divide them into ten equal piles the next morning.

That night one castaway wakes up hungry and decides to take his share early. After dividing up the coconuts he finds he is one coconut short of ten equal piles. He also notices the monkey holding one more coconut. So he tries to take the monkey's coconut to have a total evenly divisible by 10. However when he tries to take it the monkey conks him on the head with it and kills him.

Later another castaway wakes up hungry and decides to take his share early. On the way to the coconuts he finds the body of the first castaway, which pleases him because he will now be entitled to 1/9 of the total pile. After dividing them up into nine piles he is again one coconut short and tries to take the monkey's slightly bloodied coconut. The monkey conks the second man on the head and kills him.

One by one each of the remaining castaways goes through the same process, until the 10th person to wake up gets the entire pile for himself. What is the smallest number of possible coconuts in the pile, not counting the monkeys?

HintCough Math Cough

Fatalis
July 27th, 2012, 07:38 PM
Spoiler not working

Yayap
July 27th, 2012, 07:42 PM
Spoiler not working

[*spoiler=][/spoiler]

without the *

Fatalis
July 27th, 2012, 07:45 PM
Thanks Yayap ^ ^

Glip
July 27th, 2012, 07:45 PM
Ten people land on a deserted island. There they find lots of coconuts and a monkey. During their first day they gather coconuts and put them all in a community pile. After working all day they decide to sleep and divide them into ten equal piles the next morning.

That night one castaway wakes up hungry and decides to take his share early. After dividing up the coconuts he finds he is one coconut short of ten equal piles. He also notices the monkey holding one more coconut. So he tries to take the monkey's coconut to have a total evenly divisible by 10. However when he tries to take it the monkey conks him on the head with it and kills him.

Later another castaway wakes up hungry and decides to take his share early. On the way to the coconuts he finds the body of the first castaway, which pleases him because he will now be entitled to 1/9 of the total pile. After dividing them up into nine piles he is again one coconut short and tries to take the monkey's slightly bloodied coconut. The monkey conks the second man on the head and kills him.

One by one each of the remaining castaways goes through the same process, until the 10th person to wake up gets the entire pile for himself. What is the smallest number of possible coconuts in the pile, not counting the monkeys?

HintCough Math Cough

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Like this.

2519 coconuts, not including the monkey's.

Fatalis
July 27th, 2012, 07:48 PM
In order to use spoiler correctly, you must type

Insert what the spoiler is


2519 coconuts, not including the monkey's.

Like this.
Wow.. and less than 15 minutes ( it took me an hour )
Can't tell if google or math genius
Anyway, GJ!

Yayap
July 27th, 2012, 07:50 PM
2519
is your answer

edit: damn... someone beat me to it

Fatalis
July 27th, 2012, 07:52 PM
people got the answer so quickly .. I took an hour using a calculator

Edit= I think I'll posts more soon
I challenge you Glip !

Yayap
July 27th, 2012, 07:55 PM
fastest way to figure it out was start at multiples of 10 and 9 = 90 is the lowest, then move on to multiples of 90 and 8 = 360 is the lowest, then move on to multiples of 360 and 7 = 2520 is the lowest which also turns out to be a multiple of 6, 5, 4, 3, 2 and 1... subtract 1 for the monkey and you have your answer

Nick
July 27th, 2012, 08:12 PM
10 = 5 x 2
9 = 3 x 3
8 = 4 x 2
7
6 = 3 x 2
5
4 = 2 x 2
3
2

Took me awhile. Forgot to remove 3 after choosing 9.

Method: 10 is made of 5 and 2. Remove 10 if you have 5 and 2. 9 is made of 2 3s. You have only 1 3, choose 9 and remove 3.

Total coconut = 2 x 4 x 5 x 7 x 9 = 2520