Clever riddles for teens

cleanlogicsimpleclever

Two fathers and two sons went fishing one day. They were there the whole day and only caught 3 fish. One father said, that is enough for all of us, we will have one each. How can this be possible?
There was the father, his son, and his son's son. This equals 2 fathers and 2 sons for a total of 3!
72.45 %
181 votes
logicsimplecleanclever

You have two jugs, one that holds exactly 3 gallons, and one that holds exactly 5 gallons. Using just these two jugs and a fire hose, how can you measure out exactly 4 gallons of water?
Fill the 5-gallon jug to the top, and then pour it into the 3-gallon jug until the 3-gallon jug is full. You now have 2 gallons remaining in the 5-gallon jug. Pour out the 3-gallon jug, and then pour the 2 gallons from the 5-gallon jug into the 3-gallon jug. Finally, fill the 5-gallon jug to the top and pour it into the 3-gallon jug until it's full. Since there was only space left for 1 more gallon in the 3-gallon jug, you now have exactly 4 gallons in the 5-gallon jug.
72.45 %
65 votes
logicmathstorycleanclever

In the land of Brainopia, there are three races of people: Mikkos, who tell the truth all the time, Kikkos, who always tell lies, and Zikkos, who tell alternate false and true statements, in which the order is not known (i.e. true, false, true or false, true, false). When interviewing three Brainopians, a foreigner received the following statements: Person 1: I am a Mikko. Person 2: I am a Kikko. Person 3: a. They are both lying. b. I am a Zikko. Can you help the very confused foreigner determine who is who, assuming each person represents a different race?
Person 1 is a Miko. Person 2 is a Ziko. Person 3 is a Kikko.
72.39 %
103 votes
logicmathcleanclever

What is the value of 1/2 of 2/3 of 3/4 of 4/5 of 5/6 of 6/7 of 7/8 of 8/9 of 9/10 of 1000?
100. Looks hard? Don't worry, just work it backwards and you'll find it very easy.
72.34 %
56 votes
logiccleansimpleclever

A man needs to send important documents to his friend across the country. He buys a suitcase to put the documents in, but he has a problem: the mail system in his country is very corrupt, and he knows that if he doesn't lock the suitcase, it will be opened by the post office and his documents will be stolen before they reach his friend. There are lock stores across the country that sell locks with keys. The only problem is that if he locks the suitcase, he has no way to send the key to his friend so that the friend will be able to open the lock: if he doesn't send the key, then the friend can't open the lock, and if he puts the key in the suitcase, then the friend won't be able to get to the key. The suitcase is designed so that any number of locks can be put on it, but the man figures that putting more than one lock on the suitcase will only compound the problem. After a few days, however, he figures out how to safely send the documents. He calls his friend who he's sending the documents to and explains the plan. What is the man's plan?
The plan is this: 1. The man will put a lock on the suitcase, keep the key, and send the suitcase to his friend. 2. The friend will then put his own lock on the suitcase as well, keep the key to that lock, and send the suitcase back to the man. 3. The man will use his key to remove his lock from the suitcase, and send it back to the friend. 4. The friend will remove his own lock from the suitcase and get to the documents. Search: Man-in-the-middle attack
72.33 %
69 votes