Riddle #571

logic

Height marked into the tree

When Manish was three years old he carved a nail into his favorite tree to mark his height. Six years later at age nine, Manish returned to see how much higher the nail was. If the tree grew by five centimeters each year, how much higher would the nail be.
The nail would be at the same height since trees grow at their tops.
94.24 %
44 votes

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Alexander is stranded on an island covered in forest. One day, when the wind is blowing from the west, lightning strikes the west end of the island and sets fire to the forest. The fire is very violent, burning everything in its path, and without intervention the fire will burn the whole island, killing the man in the process. There are cliffs around the island, so he cannot jump off. How can the Alexander survive the fire? (There are no buckets or any other means to put out the fire)
Alexander picks up a piece of wood and lights it from the fire on the west end of the island. He then quickly carries it near the east end of he island and starts a new fire. The wind will cause that fire to burn out the eastern end and he can then shelter in the burnt area. Alexander survives the fire, but dies of starvation, with all the food in the forest burnt.
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What can go up a chimney down but not down a chimney up?
An umbrella.
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Six jugs in a row

Six jugs are in a row. The first three are filled with coke, and the last three are empty. By moving only one glass, can you arrange them so that the full and the empty glasses alternate?
Move and then pour all coke from second glass to fifth glass.
93.22 %
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Pink Island

It was a Pink Island. There were 201 individuals lived in the island. Among them 100 people were blue eyed people, 100 were green eyed people and the leader was a black eyed one. Except the leader, nobody knew how many individuals lived in the island. Neither have they known about the color of the eyes. The leader was a very strict person. Those people can never communicate with others. They even cannot make gestures to communicate. They can only talk and communicate with the leader. It was a prison for those 200 individuals. However, the leader provided an opportunity to leave the island forever but on one condition. Every morning he questions the individuals about the color of the eyes! If any of the individuals say the right color, he would be released. Since they were unaware about the color of the eyes, all 200 individuals remained silent. When they say wrong color, they were eaten alive to death. Afraid of punishment, they remained silent. One day, the leader announced that "at least 1 of you has green eyes! If you say you are the one, come and say, I will let you go if you are correct! But only one of you can come and tell me!" How many green eyed individuals leave the island and in how many days?
All 100 green eyed individuals will leave in 100 days. Consider, there is only one green eyed individual lived in the island. He will look at all the remaining individuals who have blue eyes. So, he can get assured that he has green eyes! If there were more than one green eyed people, when the first man looks at the second one with green eyes, the person didn’t leave on day the first day. It means he also has green eyes and the same rule applies to each green eyed man.
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If, Fernando + Alonso + McLaren = 6 Fernando x Alonso = 2 Alonso x McLaren = 6 Then, McLaren x Fernando =?
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90.47 %
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For all the impossible questions, Jake simply wrote "I don't know".
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If you have two coins which total 35 cents and one of the coins is not a dime, what are the two coins?
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You walk into a creepy house by yourself. There is no electricity, plumbing or ventilation. Inside you notice 3 doors with numbers on them. Once you open the doors you will die a particular way. Door #1 You’ll be eaten by a lion who is hungry. Door #2 You’ll be stabbed to death. Door #3 There is an electric chair waiting for you. Which door do you pick?
Door #3, Since There Is No Electricity To Harm You.
93.70 %
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What is the significance of the following: The year is 1978, thirty-four minutes past noon on May 6th.
The time and month/date/year are 12:34, 5/6/78.
93.05 %
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