
A crossnumber puzzle (also known as crossfigure, or figure logic) looks like a crossword puzzle, but has numbers instead of words in a grid. Crosswords focus on memory and knowledge of vocabulary. Crossnumbers focus on the handling of numbers, analysis and mathematical knowledge. Crosswords have Cryptic Crosswords with hidden meaning words. Crossnumbers have Logical Crossnumbers with hidden numbers which can be found only by logical thinking and analysis.
The Crossnumber puzzle is widely used in education and is a popular form of recreational mathematics. Logical Crossnumber (LCN) puzzles are challenging and fun because unlike crossword puzzles, most clues are in conjunction with others.
The difficulty of LCN puzzles depends on the size of their frames and the number of their black cells.
The book contains 50 LCN puzzles at 5 levels of difficulties as shown in the following table:

The objectives of the book LOGICAL CROSSNUMBER PUZZLES are
three-fold:
- Making the clues in the LCN puzzles more precise, easily and quickly understood, the numbers easily located, and complicated relationships between the numbers easily formulated.
- Making the coverage of LCN puzzles more sophisticated with mathematical knowledge, not just simple arithmetical relations between numbers.
- Making the solving of LCN puzzles more attractive, more challenging but more useful to the development of the brain and the acquisition of mathematical abilities in such areas as:
– Numerical skill: Mental and speedy arithmetical calculation,
Great numbers handling, Relative numbers handling.
– Memory improvement, Analysis skill, Perseverance practice.
The author hopes that the exciting and challenging features of Logical Crossnumber puzzles can contribute to the love of mathematics in the mind of students at high schools in Australia and around the world.
George Ho
8 March 2020
To order, contact:
Xlibris
1-800-455-039
http://www.Xlibris.com.au
Orders@Xlibris.com.au