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 5 Betsy and Patsy “We were born on the same day of the same year,” said Betsy. “And we have the same mother and father,” said Patsy. “But we’re not twins!” the two exclaimed. Can you explain? Submitted by Valentin Doable 3.5 8 All Apples On the market, mrs. Jones and mrs. Smith sell apples. Mrs. Jones sells her apples per two for 0.50 euro. The apples of Mrs. Smith are a bit smaller; she sells hers per three for 0.50 euro. At a certa ... Submitted by Valentin Doable 4.0 4 Time To Fuse You have a string-like fuse that burns in exactly one minute. The fuse is inhomogeneous, and it may burn slowly at first, then quickly, then slowly, and so on. You have a match, and no watch. How do ... Submitted by Valentin Doable 4.5 2 Good luck at an interview with Google I just came across these Google interview questions… impossible: How many golf balls can fit in a school bus? How much should you charge to wash all the windows in Seattle? How many piano tuners are ... Submitted by Valentin Hard 7.0 6 Psycho Killer While at the funeral of her mother, she met a man whom she did not know. She thought he was amazing, her dream guy, and she fell in love with him but never asked for his number and could not find him ... Submitted by Valentin Easy 3.0 9 Unfair Coin Say you have an unfair coin: a coin whose probability of flipping heads and flipping tails is unknown but nonzero. Can you design a game where you and your opponent have an equal chance of winning? Submitted by city_slick Doable 5.0 3 No if() no abs()! This is inspired by the puzzle "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 +- · / (basic arithmetic operator ... Submitted by Doodz Hard 10.0 5 Troll Toll You are on your way to visit your Grandma, who lives at the end of the valley. It’s her birthday, and you want to give her the cakes you’ve made. Between your house and her house, you have to cross ... Submitted by Aakash Easy 2.8 4 Guilty Innocence I am a drug dealer. I have been questioned by the police with all of my drugs surrounding me, but I was not arrested. Why? Submitted by Aakash Easy 2.8 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 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 5 The Female Star My first two letters are a man. The first three a woman. The first four are a brave man. And in whole I am a brave woman. Submitted by Valentin Doable 4.3 4 Gone Camping Camp Crona’s cook, Allison, was just about to begin preparing the picnic lunch for all the campers. She already knew she needed to fill 55 bowls of the same size and capacity with the same amount of fo ... Submitted by Aakash Easy 3.1 4 Clock Hands - Google Interview Question How many degrees are there in the angle between the hour and minute hands of a clock when the time is a quarter past three? Submitted by Valentin Doable 3.5 4 Boys and Girls To help solve an acute national over-population problem, a government issues a radical decree that families must stop having children as soon as they have had one son. After a while, there are some ... Submitted by Aakash Doable 5.0