Henry Ernest Dudeney (1857–1930)

The Victorian puzzle genius who made numbers, logic and geometry wonderfully entertaining.

Henry Ernest Dudeney
Old photograph of Henry digitally modernised

Henry Ernest Dudeney was one of those rare people who could make mathematics feel like a story, a joke, a challenge and a mystery all at once. Born in Sussex in 1857, he did not follow the usual academic path to mathematical fame. Instead, he worked in ordinary jobs, wrote for newspapers and magazines, and developed an extraordinary talent for turning everyday situations into puzzles that made people stop, think and smile.

His puzzles appeared at a time when magazines were a major form of popular entertainment, and Dudeney became one of the great masters of recreational mathematics. Readers encountered his problems in columns such as “Perplexities” in The Strand Magazine, and later in collections including The Canterbury Puzzles and Amusements in Mathematics. His best puzzles were not merely sums dressed up in words; they were little worlds, full of travellers, shopkeepers, chessboards, coins, ropes, animals, bridges and curious arrangements that invited the reader to reason their way to a hidden truth.

than a century later, Dudeney’s work still feels fresh because he understood something every good teacher knows: people enjoy thinking when the question is intriguing enough. His legacy is not just a list of clever answers, but a way of presenting mathematics as play, exploration and surprise. Many of today’s puzzle creators, teachers and maths enthusiasts are still following paths that he helped to mark out.

Transum versions of Dudeney Puzzles

Drag-and-Drop

The Miller's Puzzle

The Miller's Puzzle

This is an interactive version of the puzzle described by Henry Ernest Dudeney in The Canterbury Puzzles

The short web address is:

Transum.org/go/?Num=344

Drag-and-Drop

The Broken Chessboard

The Broken Chessboard Puzzle

The chessboard has been broken into 13 pieces. Can you put it back together?

The short web address is:

Transum.org/go/?Num=547

Levelled Exercises

Squareas

Squareas

Square areas - some are shown and others can be deduced to find the unknown

The short web address is:

Transum.org/go/?Num=1168

Lesson Starter

Book Worm

Book Worm

Calculate the length of the bookworm's meal if it eats through the front cover to the back cover of a set of encyclopaedias.

Transum.org/go/?Start=February2

Dudeney: Amusements in Mathematics, No. 420, "The Industrious Bookworm"

Noel Stocking's Rich

Noel Stocking's Rich

December 2017

Noel wrote down the pence for pounds and the pounds for pence. After giving 50p to his sister, his record was exactly double his bank balance.

Transum.org/Newsletter/?p=340

Dudeney: 536 Puzzles & Curious Problems, No. 1, "Concerning a Check"

Cupcakes and Easter Eggs

Cupcakes and Easter Eggs

April 2023

Cupcakes at three prices, seven pounds to spend and as many boys as girls. How many cakes did each child receive?

Transum.org/Newsletter/?p=533

Dudeney: 536 Puzzles & Curious Problems, No. 5, "Buying Buns" (also Amusements in Mathematics, No. 36, "Buying Apples")

Divided Dartboard

Divided Dartboard

September 2023

A dartboard breaks into two pieces so that the sum of the numbers on one piece is twice the sum of the numbers on the other.

Transum.org/Newsletter/?p=538

Dudeney: 536 Puzzles & Curious Problems, No. 49, "The Broken Clock Face"

Trains Together

Trains Together

October 2020

Trains leave Aberdale and Bluffington at the same time, travelling at 90 and 110 kilometres per hour. How far apart are they half an hour before they meet?

Transum.org/Newsletter/?p=503

Dudeney: 536 Puzzles & Curious Problems, No. 94, "A Little Train Puzzle"

A Penguin and a Crab

A Penguin and a Crab

March 2026

They set off towards each other's starting points at the same time and pass at 11am. Given their arrival times, when did the waddling and scuttling begin?

Transum.org/Newsletter/?p=568

Dudeney: Amusements in Mathematics, No. 68, "The Two Trains"

Keith and Kath

Keith and Kath

February 2021

Their combined age is 91. Keith is now twice as old as Kath was when Keith was as old as Kath is now. How old are they?

Transum.org/Newsletter/?p=507

Dudeney: Amusements in Mathematics, No. 46, "Mary and Marmaduke" (also famous as Sam Loyd's "How Old Is Ann?")

Twice the Wig

Twice the Wig

June 2024

A judge is twice as old as her wig was when she was as old as her wig is now. The sum of their ages is 56. How old is the judge?

Transum.org/Newsletter/?p=547

Dudeney: Amusements in Mathematics, No. 46, "Mary and Marmaduke" (also famous as Sam Loyd's "How Old Is Ann?")

The Price of Easter Eggs

The Price of Easter Eggs

April 2025

Two free eggs were thrown in with the £3.60 purchase, bringing the cost down by 30p per dozen. How many eggs were bought?

Transum.org/Newsletter/?p=557

Dudeney: Amusements in Mathematics, No. 21, "A Deal in Apples"

A Hundred from 4 Sevens

One Hundred from Four Sevens

March 2023

Can you make 100 from four sevens and a zero using any mathematical symbols?

Transum.org/Newsletter/?p=532

Dudeney: Amusements in Mathematics, No. 95, "The Four Sevens"

Bookworm's Breakfast

Bookworm's Breakfast

October 2015

A bookworm eats from the front cover of volume one to the back cover of volume ten. How long is the bookworm's meal?

Transum.org/Newsletter/?p=145

Dudeney: Amusements in Mathematics, No. 420, "The Industrious Bookworm"

Santa's Window

Santa's Window

December 2021

Santa wants to make a window twice its original area without increasing either its height or its width. How can that be done?

Transum.org/Newsletter/?p=517

Dudeney: 536 Puzzles & Curious Problems, No. 271, "The Square Window"

Marathon Average Speed

Marathon Average Speed

May 2018

Sue runs the first half of the marathon at 5 miles per hour. How fast must she run the second half to average 10 miles per hour overall?

Transum.org/Newsletter/?p=393

Dudeney: Amusements in Mathematics, No. 67, "Average Speed"

Sharing Trophies

Sharing Trophies

March 2025

Trophies are to be shared in halves, thirds and eighths, which only becomes possible when one extra trophy is borrowed. How many trophies were there?

Transum.org/Newsletter/?p=556

Dudeney: 536 Puzzles & Curious Problems, No. 172, "The Seventeen Horses" (an ancient inheritance puzzle)

Pumpkin Price Puzzle

Pumpkin Price Puzzle

October 2024

Pumpkins bought at 4 for £20 in one shop and 6 for £20 in another. What was the mean number of pumpkins bought for £20?

Transum.org/Newsletter/?p=551

Dudeney: 536 Puzzles & Curious Problems, No. 23, "The Missing Penny" (which Dudeney introduces as "an ancient puzzle")

Carrot-eating Critters

Carrot-eating Critters

August 2019

Twenty animals eat twenty carrots between them. How many donkeys, goats and rabbits are there?

Transum.org/Newsletter/?p=489

Dudeney: 536 Puzzles & Curious Problems, No. 11, "Market Transactions" (his rendering of the ancient "hundred fowls" problem)

Eva's Eggs

Eva's Eggs

May 2020

Each customer buys half of Eva's remaining eggs plus half an egg, yet no egg is ever broken. How many eggs did she take to market?

Transum.org/Newsletter/?p=498

Dudeney: The Canterbury Puzzles, No. 88, "The Eccentric Market-woman" (his embellishment of this older puzzle)

Weighted Puzzle

Weighted Puzzle

July 2022

Four weights on a balance scale can weigh any whole number of pounds from 1 to 40. What could those four weights be?

Transum.org/Newsletter/?p=524

Discussed by Dudeney in Amusements in Mathematics, credited by him to Bachet de Méziriac (1612)

Solvitude Festival

Solvitude Festival

June 2026

Help Madam Mushnik distribute the coins so that the three festival rules are obeyed.

Transum.org/Newsletter/?p=571

Dudeney: Amusements in Mathematics

Mrs Brambleshaw's Apples

Mrs Brambleshaw's Apples

July 2026

How many young Pickles were there if they all received the same amount of fruit?

Transum.org/Newsletter/?p=572

Dudeney: 536 Puzzles & Curious Problems, No. 5, "Buying Buns" (also Amusements in Mathematics, No. 36, "Buying Apples")

Speakers with Blue Teeth

Speakers with Blue Teeth

May 2025

The shop assistant reversed the pounds and pence in Freddie's refund. After buying a £1.50 drink he had exactly twice the cost of the speaker.

Transum.org/Newsletter/?p=558

Dudeney: 536 Puzzles & Curious Problems, No. 1, "Concerning a Check"

The Dudeney Puzzle Catalogue

An index of 1786 puzzles by Henry Ernest Dudeney

Puzzle Name Topic Book PDF File No. Dudeney's Section
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