Puzzle 1
The river Pregel ran through the town of Konigsberg. In the river were two islands, connected to each other and the rest of the city by seven bridges.
The residents of Konigsberg challenged each other to walk through the city, and cross each of the seven bridges exactly once.
Can you find a path that they might have taken?
This is the 'Seven Bridges of Konigsberg' puzzle, tackled by Leonhard Euler in 1736.
Puzzle 2
Starting with HATE, change one letter at a time until you have the word LOVE-
Each change leaves the other letters in their original places and must result in a proper word-
What is the minimum number of steps required to achieve this change?
There are four different answers using common words, can you find all four?
hate
----
----
----
love
Puzzle 3
My 6, 7, 3 is a tear to a newspaper.
My 5, 4, 1 is damper than moist.
My 1, 7, 6, 4 is to become weary.
My 5, 7, 6, 9 helps electricity to flow.
My 8, 10, 2 is an attempt at this puzzle.
My whole could have been used to create this puzzle.
Puzzle 4
Can you complete this grid of letters?
Each line is a valid 5-letter word with its first and last letters missing.
The missing letters form a word when read downwards, and the same word appears both at the start and at the end.
What is the missing word?
| I | N | E | ||
| R | O | D | ||
| Y | L | O | ||
| O | A | S | ||
| E | A | T |
Note: this puzzle is not interactive, and the squares cannot be clicked.