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 3 The Bookworm Looking onto a shelf you see three books each labeled Volume 1, Volume 2, and Volume 3 respectively. Each book is 2.5 inches thick; that is the pages are 2 inches, and each cover .25 inches. A bo ... Submitted by Aakash Doable 4.9 8 Non-Adaptive 12 Identical Balls Okay - so I posted this puzzle to reddit a few weeks ago and one guy had the following comment: Same problem, but your solution must be non-adaptive. IOW, specify the weighings that you will make up f ... Submitted by Aakash Hard 9.0 10 Fork in the road You are walking down a road and arrive at a fork that splits the road into two separate paths. When you reach, you meet two identical twins, each standing at the edge of one of the two paths. You h ... Submitted by Aakash Doable 6.0 46 Charlie and the Chocolate Factory Charlie once visited chocolate factory to buy some chocolates.Chocolate cost Rs. 3 each and he had only Rs. 45.He was disappointed. He wanted more. But when he reached the factory he was amazed. There ... Submitted by Mikit Kanakia Easy 2.4 56 All the King's Wine So there's this king. Someone breaks into his wine cellar where he stores 1000 bottles of wine. This person proceeds to poison one of the 1000 bottles, but gets away too quickly for the king's guard ... Submitted by Aakash Hard 7.5 14 Coin Flip On Monday, you flip a coin all day. You start flipping it until you see the pattern Head, Tail, Head. You record the number of flips required to reach this pattern, and start flipping again (and co ... Submitted by Aakash Doable 6.0 45 The Sinking Island You and 3 friends are on an island that is sinking. There is one bridge from the island to the mainland that supports at most 2 people at once. However, it's dark outside so anyone crossing the bridge ... Submitted by Ravi Doable 4.3 37 No if() Only abs() Given two variable a and b, construct a function f(a,b) which return the maximum one in {a,b}. You can only use +- · / and abs() (to take the absolute value). NO if() is allowed in your construction. ... Submitted by MoralMachine Doable 5.8 28 12 Identical Balls You have 12 identical balls. One of them is slightly different in weight than the rest. You have three weighs of a balance scale to determine which ball is different and whether it is heavier or li ... Submitted by Valentin Doable 6.2 17 Multiples of 8 plus 1 Squaring the first several odd numbers reveals the following pattern: 3 squared = 8 + 1 5 squared = 24 + 1 7 squared = 48 + 1 8, 24, and 48 are all multiples of 8. Does this pattern hold for all squa ... Submitted by Heather Moore Doable 4.5 12 Gold or silver? What weighs more, a pound of silver or a pound of gold? Submitted by Jango Easy 2.0 18 Cocktail Party You are observing a cocktail party that has seven guests. You notice that each guest shakes hands with one another once they meet, but never again. How many handshakes occurred during the cocktail part ... Submitted by Nikhil Easy 2.4 1 Stuck in a brick building A man is stuck inside an all brick building (floor, ceiling, and walls are all brick), that has no windows and no doors, and inside with him he has only a wooden board and a saw, how does he get out? ... Submitted by Valentin Doable 5.3 13 Black and White Hats There are 100 prisoners in jail. Their guards decide to play a game with them. Here's what happens: 1) The prisoners are lined up in a single file, front to back, such that the prisoner at the back of ... Submitted by Aakash Hard 8.5 21 Odd Pills Your pharmacist gives you 5 jars filled with pills. The pills contained in each jar have an identical appearance and size (i.e. if you mixed all of the pills you wouldn't be able to tell them apart). ... Submitted by Jay Elliott Doable 3.6