Puzzle: Every day, Jack arrives at the train station from work at 5 pm. His wife leaves home in her car to meet him there at exactly 5 pm, and drives him home. One day, Jack gets to the station an hour early, and starts walking home, until his wife meets him on the road. … Read More →

## 2 Player and N Coin – Strategy Puzzle

Puzzle: There are n coins in a line. (Assume n is even). Two players take turns to take a coin from one of the ends of the line until there are no more coins left. The player with the larger amount of money wins. Would you rather go first or second? Does it matter? Assume … Read More →

## Minimum no Of Aircraft Puzzle

Puzzle: On Bagshot Island, there is an airport. The airport is the home base of an unlimited number of identical airplanes. Each airplane has a fuel capacity to allow it to fly exactly 1/2 way around the world, along a great circle. The planes have the ability to refuel in flight without loss of speed … Read More →

## Chickens and Rabbits | Math Puzzle

Puzzle: There are several chickens and rabbits in a cage (with no other types of animals). There are 72 heads and 200 feet inside the cage. How many chickens are there, and how many rabbits? Puzzle Solution: Let c be the number of chickens, and r be the number of rabbits. r + c = … Read More →

## Nugget Numbers | Math Brain Teaser

Puzzle: At McDonald’s you can order Chicken McNuggets in boxes of 6,9, and 20. What is the largest number of nuggets that you cannot order using any combination of the above? Puzzle Solution: 43 It is possible to achieve all multiples of 3 that are bigger than 6, through the 6s and 9s alone. Adding … Read More →

## The Pill Problem | Hard Brain Teaser

Puzzle: This is very hard brain teaser. A man has a medical condition that requires him to take two kinds of pills, call them P1 and P2. The man must take one P1 pill and one P2 pill each day, or he will die. If he takes more than 1 pill of the same kind … Read More →

## How to Check if a given Number is Fibonacci number?

In mathematics, the Fibonacci numbers or Fibonacci sequence are the numbers in the following integer sequence: 1,1,2,3,5,8,13,21,34,55,89,144.. A simple way is to generate Fibonacci numbers until the generated number is greater than or equal to ‘x’. Following is an interesting property about Fibonacci numbers that can also be used to check if a given number … Read More →

## How Much Money He had Initially ?

Puzzle: One person has some money in his pocket, He visits four temple on the way. As soon as he enters a temple, his money gets double and he offers Rs. 100 in each temple thus his pocket gets empty after he returns from the fourth temple. Now the question is how much money he … Read More →

## Check Whether a Given Point Lies inside a Triangle or not

Given three corner points of a triangle, and one more point P. Write a function to check whether P lies within the triangle or not. The program needs to read the values of three coordinates A(x1,y1) B(x2,y2) C(x3,y3) as well as another coordinate P(x,y) and determine whether this point is inside a triangle formed from … Read More →

## When is Cheryl’s Birthday?

So when is Cheryl’s birthday? That’s a question confounding thousands of people around the world Monday as a test question from Singapore goes viral. Puzzle: 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 May 16 … Read More →

## Flower Pot Puzzle

Puzzle: Sara has 6 flower pots, each having a unique flower. Pots are arranged in an arbitrary sequence in a row. Sara rearranges the sequence each day but not two pots should be arranged adjacent to each other which were already adjacent to each other in previous arrangement. How many days she can do this … Read More →

## Prove that p^2 – 1 is Divisible by 24

Problem: Prove that p2 – 1 is divisible by 24 if p is a prime number greater than 3? Solution: The most elementary proof , without explicitly mentioning any number theory: out of the three consecutive numbers p–1, p, p+1, one of them must be divisible by 3; also, since the neighbors of p are … Read More →

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