## The Best Aplusclick Puzzle 2020

January 5, 2021 Leave a comment

Here they go

Math and Logic Puzzles

March 1, 2020 Leave a comment

There was a tradition in old Russia. A would-be bride gathers six long pieces of straw and grasp them in her hand. She then randomly ties pairs of knots on the top and the bottom. Since there are six blades of grass sticking out above and below the hand, she will tie three knots on the top and three knots on the bottom. If she forms one big ring, she gets married soon.

Estimate the probability that the girl will get married soon.

*The problem is mentioned in The New York Times NUMBERPLAY and it is credited to Sunil Singh.*

February 16, 2020 Leave a comment

Seven secret agents are on payroll of a government.

Secret agent 001 spies on a secret agent who spies on secret agent 002,

who spies on a secret agent who spies on secret agent 003,

who spies on . . . spies on secret agent 007

who spies on a secret agent who spies on secret agent 001.

Who spies on secret agent 007?

January 13, 2020 Leave a comment

Gerry has several pets at home.

All of them are dogs, except for three.

All of them are cats, except for four.

All of them are tortoises, except for five.

How many dogs does he have?

December 1, 2019 Leave a comment

These are the Best Puzzles published at www.aplusclick.org in 2019.

October 6, 2019 Leave a comment

A drinks dispenser has three labelled buttons: JUICE, SODA, and LUCKY. If you press LUCKY you are supposed to get either juice or soda with equal probability.

Each button is wired to exactly one of these functions, but each function is not necessarily wired to exactly one button.

Assuming that you are clever, but unlucky, how many button presses are required to establish exactly which button does which function?

Check the answer

August 20, 2019 Leave a comment

It is the first day of a new school year, and this class has only 10 students. Ashley has 9 friends, Betty has 8, Caleb has 7, Derek has 6, Elaine has 5, Graham has 4, Henri has 3, Ivana has 2, Julie has 1. Name one of Fred’s friends.

In a group of 4 school children, each child has exactly two friends, just one of which is their best friend. What is the minimum possible number of children for whom their best friend is also that friend’s best friend?

It is the first day of a new school year, and this class has only 10 students. Ashley has 9 friends, Betty has 8, Caleb has 7, Derek has 6, Elaine has 5, Graham has 4, Henri has 3, Ivana has 2, Julie has 1. How many friends does Fred have?

It is the first day of a new school year, and this class has only 5 students. Amy has no friends yet. Betty has one friend. Chris has three friends. Derek has two friends. How many friends does Ellie have?

In a group of five students, Ann has one real friend among them, Betty has two, Craig has three, and Dianna has two. How many real friends does Edgar have in the group?

July 12, 2019 1 Comment

How to choose the shortest road that connects several towns. This is a story about local and global minimums. Excellent presentation of soapy films.

April 28, 2019 Leave a comment

Find a mistake. Think differently!

Find more logic puzzles for all ages in Think Outside the Box collection of puzzles.

December 1, 2018 Leave a comment

New challenges:

What is the easiest way to make it correct? Answer

In what Olympic sport does the winner cross the line facing backwards? Answer

What time is it? Answer

What is the necessary mirror size? Answer

Find all 18 best puzzles at