Brain Teasers & Puzzles

A bridge will collapse in 17 minutes.
4 people want to cross it before it will collapse. It is a dark night and there is only one torch between them.
Only two people can cross at a time.
“A” takes a minute to cross.
“B” takes 2 minutes.
“C” takes 5
and “D” takes 10 minutesHow do they all cross before the bridge collapses?
View SolutionSubmit Solution 19667 views
 2 answers
 3 votes

Albert and Bernard just became friends with Cheryl, and they want to know when her birthday is. Cheryl gives them a list of 10 possible dates.
May 15 16 19
June 17 18
July 14 16
August 14 15 17
Cheryl then tells Albert and Bernard separately the month and the day of her birthday, respectively.
Albert: I don’t know when Cheryl’s birthday is, but I know that Bernard does not know, too.
Bernard: At first, I didn’t know when Cheryl’s birthday is, but I know now.
Albert: Then I also know when Cheryl’s birthday is.
When is Cheryl’s birthday?
View SolutionSubmit Solution 3307 views
 1 answers
 0 votes

The owner of a banana plantation has a camel. He wants to transport his 3000 bananas to the market, which is located after the desert. The distance between his banana plantation and the market is about 1000 kilometer. So he decided to take his camel to carry the bananas. The camel can carry at the maximum of 1000 bananas at a time, and it eats one banana for every kilometer it travels.
What is the most bananas you can bring over to your destination?
View SolutionSubmit Solution 9507 views
 1 answers
 0 votes

You have 100 doors in a row that are all initially closed. you make 100 passes by the doors starting with the first door every time. the first time through you visit every door and toggle the door (if the door is closed, you open it, if its open, you close it). the second time you only visit every 2nd door (door #2, #4, #6). the third time, every 3rd door (door #3, #6, #9), ec, until you only visit the 100th door.
What state are the doors in after the last pass? Which are open which are closed?
Puzzle asked in: Google,Adobe,Amazon,OracleView SolutionSubmit Solution 10385 views
 2 answers
 0 votes

There is a building of 100 floors
If an egg drops from the Nth floor or above it will break.
If it’s dropped from any floor below, it will not break.
You’re given 2 eggs.
Find NHow many drops you need to make?
What strategy should you adopt to minimize the number egg drops it takes to find the solution?View SolutionSubmit Solution 160436 views
 15 answers
 4 votes

You are blindfolded and 10 coins are place in front of you on table.
You are allowed to touch the coins, but can’t tell which way up they are by feel. You are told that there are 5 coins head up, and 5 coins tails up but not which ones are which.
How do you make two piles of coins each with the same number of heads up?
View SolutionSubmit Solution 13330 views
 1 answers
 0 votes

Prove that p^2 – 1 is divisible by 24 if p is a prime number greater than 3?
View SolutionSubmit Solution 5628 views
 1 answers
 1 votes

 6475 views
 1 answers
 0 votes

 8440 views
 1 answers
 0 votes

 3797 views
 1 answers
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