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wiki:donuts:fall2014 [2014/11/18 13:13]
jmb438
wiki:donuts:fall2014 [2014/12/17 14:56] (current)
jmb438
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 [[wiki:​donuts:​fall2014:​answers:​triple|answer]] ​ [[wiki:​donuts:​fall2014:​answers:​triple|answer]] ​
  
 +===== Pirates =====
 +
 +Five pirates raid the ship of a wealthy bureaucrat and steal his trunk of gold pieces. By the time they get the trunk aboard, dusk has fallen, so they agree to split the gold the next morning.
 +
 +But the pirates are all very greedy. During the night one of the pirates decides to take some of the gold pieces for himself. He sneaks to the trunk and divides the gold pieces into five equal piles, ​ with one gold piece left over. He puts the gold piece in his pile, hides it, puts the other four piles back in the trunk, and sneaks back to bed. 
 +
 +One by one, the remaining pirates do the same. They sneak to the trunk, divide the coins into five piles, with always one coin left over. Each pirate puts the gold coin in his own pile, hides it, and  puts the remaining four piles back in the trunk.
 +
 +What is the smallest number of coins there could have been in the trunk originally? ((Richard Black, Nov 15))
 +
 +[[wiki:​donuts:​fall2014:​answers:​pirates|answer]] ​
 +
 +===== Sticks =====
 +
 +There are two sticks. Each stick will burn in 1 hr, but the rate at which it burns is unknown and non-uniform. How can you use these sticks to time 15 minutes? ((Wu Yifeng, Dec 1))
 +
 +[[wiki:​donuts:​fall2014:​answers:​sticks|answer]] ​
 +
 +===== Camel Herders =====
 +
 +2 camel herders (Jack and Bill) decide to sell their camels and buy some sheep. When they get to the market, they find out that the price to sell a camel is equal to the total number of camels in your herd when you arrive at the market. To increase their money, they decide to pool their camels into one big herd before they arrive, then sell them all. They take the money and buy sheep at $10 each. After they buy the sheep, they have some money left over and use all of it to buy one goat. It turns out that when they split the sheep into two equal herds, there is one extra sheep. Jack has the larger herd and tells Bill that he can have the goat. Bill says this is still not a fair split, so Jack takes one of his own dogs and gives it to Bill. Bill and Jack both agree that this is now a fair split. How much is one dog worth? ((Josh Sypherd, Dec 8))
 +
 +[[wiki:​donuts:​fall2014:​answers:​camels|answer]] ​
 +
 +===== Square Digits =====
 +
 +Let N be some two-digit number, with the digits denoted as A and B.
 +Let N<​sup>​2</​sup>​ be a three-digit number with the digits denoted as C, A and B.
 +  N   ​= ​ AB
 +  N^2 = CAB
 +
 +What digit does C represent? ((Dr. Jeffs, Dec 16))
 +
 +[[wiki:​donuts:​fall2014:​answers:​square|answer]] ​
  
 ===== Questions Asked ===== ===== Questions Asked =====
 | Junming Diao | 2 | | Junming Diao | 2 |
-| Jay Brady | +| Jay Brady | 
-| Josh Sypherd | +| Josh Sypherd | 
-| Dr. Jeffs | +| Dr. Jeffs | 
-| Richard Black | |+| Richard Black | |
 | Dr. Warnick ​ | 1 | | Dr. Warnick ​ | 1 |
-| Mitch Burnett | 0 | +| Wu Yifeng | |
-| Mark Ruzindana | 0 | +
-| Wu Yifeng | |+
wiki/donuts/fall2014.1416341589.txt.gz · Last modified: 2014/11/18 13:13 by jmb438