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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?
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 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 1,284.9K 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 1,443.3K views
 15 answers
 2 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 1,287.7K views
 1 answers
 1 votes

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

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 1,277.2K views
 2 answers
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People are waiting in line to board a 100seat airplane. Steve is the first person in the line. He gets on the plane but suddenly can’t remember what his seat number is, so he picks a seat at random. After that, each person who gets on the plane sits in their assigned seat if it’s available, otherwise they will choose an open seat at random to sit in.
The flight is full and you are last in line. What is the probability that you get to sit in your assigned seat?
View SolutionSubmit Solution 1,345.8K views
 10 answers
 0 votes