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 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 4 Attic Light Switch A downstairs panel contains three on-off switches. One of them controls the lamp in your attic. Using only ONE trip up to the attic, how do you determine which switch controls the lamp? Submitted by Aakash Doable 4.7 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 9 The Monty Hall Problem You’re on a game show, and you’re given the choice of three doors: Behind one door is a car and behind the other two doors are goats. You pick a door, say No. 1, and the host, who knows what’s behind ... Submitted by Ravi Doable 5.5 7 The Neighbourhood People say Einstein suggested that 98% of the world’s population couldn’t figure out the answer to this puzzle. It is not for the faint of heart: There are 5 houses each with a different color. Th ... Submitted by Aakash Hard 7.5 1 4 buttons and a light bulb There are two rooms, in one room there is a light bulb, and in the other there is a round table, with 4 buttons arragned in a square on it. Each button may be on or off, and the light bulb will be on o ... Submitted by TulkinRB Hard 8.0