## The Best Aplusclick Puzzle 2020

January 5, 2021 Leave a comment

Here they go

Math and Logic Puzzles

April 5, 2020 Leave a comment

There are 5 counters in a bag. Three are Argentinean (blue) and two are Brazilian (green). Three counters are randomly picked out of the bag, one by one. They are not returned to the bag.

What probability is higher?

A. The probability of choosing * three Argentinean counters* in a row.

B. The probability of choosing * two Brazilian counters* in a row and then one Argentinean counter.

Find the answer.

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.

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.

January 2, 2019 Leave a comment

Big Ben is the nickname for the Great Bell of the clock at the north end of the Palace of Westminster in London, United Kingdom.

A pile of old coins helps to keep the clock mechanism accurate. The pennies are stacked on the pendulum of the clock and have acted as weights. Adding or taking away coins effects the pendulum’s centre of mass and the rate at which it swings. A single penny will change the clock’s speed by two fifths of one second per day.

How does the weekly time change if we add 5 pennies to the pendulum?

At twelve o’clock, twelve chimes ring from the great bell in 44 seconds. ## How long does it takes to ring the hours at 15:00 ?

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