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.
91.04 %
47 votes

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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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The Pope, Beyonce, Barack Obama, and Bill Gates are on the same plane. There are only 3 parachutes left for the 4 of them. Obama says: "As the President, I think I should have the right to have a parachute, because I rule millions of people in the greatest nation of all." Beyonce says: "As one of the greatest singers of all-time, I think I should deserve to be safe. I bring tears and laughter to millions of people, and I'm an important contributor to pop music." Bill Gates says: "As one of the richest successful company owners, I think I should live because I'm on top of the economics cycle, creating jobs and incomes for millions of people. I am a wealthy and intelligent man." Finally, the Pope says: "I'm an old, religious man. I lived a life that's full, I helped millions of people find their way through God, I'm ready to let go of a parachute and to face my fate." Which one of them will abandon the parachute and die?
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92.28 %
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Three ants are sitting at the three corners of an equilateral triangle. Each ant starts randomly picks a direction and starts to move along the edge of the triangle. What is the probability that none of the ants collide?
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Joe bets Tony $100 that he can predict the score of the football game before it starts. Tony agrees, but loses the bet. Why did Tony lose the bet?
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Five friends have their gardens next to one another, where they grow three kinds of crops: fruits (apple, pear, nut, cherry), vegetables (carrot, parsley, gourd, onion) and flowers (aster, rose, tulip, lily). They grow 12 different varieties. Everybody grows exactly 4 different varieties Each variety is at least in one garden. Only one variety is in 4 gardens. Only in one garden are all 3 kinds of crops. Only in one garden are all 4 varieties of one kind of crops. Pears are only in the two border gardens. Paul's garden is in the middle with no lily. Aster grower doesn't grow vegetables. Rose grower doesn't grow parsley. Nuts grower has also gourd and parsley. In the first garden are apples and cherries. Only in two gardens are cherries. Sam has onions and cherries. Luke grows exactly two kinds of fruit. Tulips are only in two gardens. Apples are in a single garden. Only in one garden next to the Zick's is parsley. Sam's garden is not on the border. Hank grows neither vegetables nor asters. Paul has exactly three kinds of vegetable. Who has which garden and what is grown where?
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Flipping Lockers

There are 1 million closed school lockers in a row, labeled 1 through 1,000,000. You first go through and flip every locker open. Then you go through and flip every other locker (locker 2, 4, 6, etc...). When you're done, all the even-numbered lockers are closed. You then go through and flip every third locker (3, 6, 9, etc...). "Flipping" mean you open it if it's closed, and close it if it's open. For example, as you go through this time, you close locker 3 (because it was still open after the previous run through), but you open locker 6, since you had closed it in the previous run through. Then you go through and flip every fourth locker (4, 8, 12, etc...), then every fifth locker (5, 10, 15, etc...), then every sixth locker (6, 12, 18, etc...) and so on. At the end, you're going through and flipping every 999,998th locker (which is just locker 999,998), then every 999,999th locker (which is just locker 999,999), and finally, every 1,000,000th locker (which is just locker 1,000,000). At the end of this, is locker 1,000,000 open or closed?
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