Big Ben Maths

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.  bigben

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 ?



18 Best Aplusclick Puzzles of 2018

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

17 Best Puzzles of 2017


Aplusclcik team chose 17 Best Puzzles of 2017.

They are:

What country has the lowest birth rate in the World?


If certain words in this question are spelt wrong, how many of the eighteen words are spelt wrong?


A claustrophobic gentleman chooses his place in the train that will enter a tunnel just after the station. Where is the best place for him?2017Aplusclick3



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Cat, Rat, Hat, and Mat




Mary has a cat, and a rat, and a hat, and a mat.

If the cat is on the mat, and rat is in the hat, but the hat is on the mat, where is the rat?

This is a simple puzzle asked by Leslie Green, who collects dozens challenging puzzles.  The collection of Leslie Logic and Math Puzzles is presented at the website Aplusclick. It’s worth to try the challenging questions.




Selfie Math

Jim is going on a tour around the world. He has 5 tops, 4 bottoms, and 3 pairs of footwear. He wants to post a selfie everyday to show different places and his different outfits to his girl-friend Mary, who stays at home. He does not want to wear the same outfit twice. ## For how many days does he have enough clothing?


Leslie Green gives the answer : 96 days.

Can you explain why it is 96? What is logic behind?



Car Owner’s Puzzles

Can a specific subject provokes interest to Math?

For example, cars. How much does the gas cost in a month? What speed to choose? When do I need to change the tires? How to be on time? How much do I pay for a car during its life? . . .


What are other intersting subjects? Finance? Love? Sport?