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 3 Brain Teaser 56 Answer Yes or No to this brain teaser Submitted by raiseyouriq Easy 2.8 3 Tooth Paste, : Profit There are 2 Persons, Who Saves Money. One person Bought a tooth Paste of 100 gms, for Rs. 40. The second person Buys, Two 50 gms for Rs. 20 each. at same shop, the same company of Pastes. No Extra past ... Submitted by Sachin Prabhu Doable 6.0 2 What is the sum of 1+2+3+4+5 . . . (forever)? What is the sum of 1 + 2 + 3 + 4 . . . all the way to infinity? Submitted by Tarun245 Hard 8.0 5 Lab Rat on the Run Consider a lab rat in a maze. There are four paths that can be taken with equal probability. Path A leads to exit in 5 minutes. Path B leads back to start and takes 8 minutes. Path C leads to exit in 3 ... Submitted by Yiğit Oktar Doable 6.0 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 4 Cut the pizza into 11 equal slices with a wrist watch Tools: (1) A wrist watch and (2) a normal knife Goal: Slice a pizza into 11 equal pieces Submitted by MoralMachine Doable 6.0 2 How far can you go? You have a 4 wheels car and a spare tire in the trunk. The tire being used will be worn off for 1/4 part of it per mile (completely wear out for 4 miles) How to make use of the spare tire to go as fa ... Submitted by MoralMachine Doable 5.2 6 Binary 5 digits What is the base 10 equivalent of the highest 5 digit binary number? Submitted by Heather Moore Easy 2.0 8 Survivor There are 1500 people sitting around a circular table. They are numbered in a regular manner (1 to 1500 along the table). Now, the 1st person gets a sword and kills the 2nd person. He then gives the s ... Submitted by Shaheen Hard 8.5 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 9 1978 The year 1978 is such that the sum of the first two digits and the latter two digits is equal to the middle two digits, i.e. 19 + 78 = 97. What is the next year (after 1978) for which this is true? Submitted by Ryan Miller Doable 6.6 5 Matchsticks This is a classic Martin Gardner puzzle. See the picture - the four matchsticks represent a martini glass and the match head represents an olive. Move just two matches so that the glass is reformed bu ... Submitted by Aakash Doable 3.6 5 Count The Bits Write a function that counts the number of bits in an integer that are set to 1 that is linear in time complexity in the worst case, but sub-linear on average. Submitted by Jay Elliott Hard 7.6 6 Partitioning a set In how many ways can a set of r objects be partitioned into subsets of k objects such that: all subsets are mutually exclusive each of k-object subset appears in exactly one of the partitions [Partit ... Hard 8.7 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